John Hancock

Preferred Income Fund

Ticker: HPI
Semiannual report 1/31/17

Dear shareholder,

Financial markets are by their very nature unpredictable, but few market observers could have imagined the dramatic twists and turns that would come to characterize the end of 2016 and the beginning of 2017. Donald Trump's victory in November's presidential election sent both U.S. equity prices and bond yields sharply higher. The S&P 500 Index, NASDAQ, and Dow Jones Industrial Average each set new all-time highs in the final weeks of the year, and stocks continued to rally in January.

Much of this change in market sentiment from wariness to a more considered optimism has been fueled by the prospect of the Trump administration implementing a variety of pro-growth reforms. Given that Republicans control the White House and hold majorities in both houses of Congress, it is likely that change is indeed on the horizon. But the country remains deeply divided on many issues, and attempts by the new administration to implement some of its more controversial campaign promises will give investors plenty to worry about in the months ahead.

One of your best resources for dealing with market uncertainty is your financial advisor, who can help ensure your portfolio is sufficiently diversified to meet your long-term objectives and to withstand the inevitable bumps along the way.  

On behalf of everyone at John Hancock Investments, I'd like to take this opportunity to thank you for the continued trust you've placed in us.

Sincerely,

Andrew G. Arnott
President and Chief Executive Officer
John Hancock Investments

The S&P 500 Index tracks the performance of 500 of the largest publicly traded companies in the United States. It is not possible to invest directly in an index. Diversification does not guarantee a profit or eliminate the risk of a loss.

This commentary reflects the CEO's views, which are subject to change at any time. Diversification does not guarantee investment returns and does not eliminate risk of loss. All investments entail risks, including the possible loss of principal. For more up-todate information, you can visit our website at jhinvestments.com.

John Hancock
Preferred Income Fund

Table of contents

2		Your fund at a glance
4		Discussion of fund performance
8		Fund's investments
13		Financial statements
17		Financial highlights
18		Notes to financial statements
26		Additional information
26		Shareholder meeting
27		More information

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       1

INVESTMENT OBJECTIVE

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The fund seeks to provide a high level of current income consistent with preservation of capital. The fund's secondary investment objective is to provide growth of capital to the extent consistent with its primary objective.

AVERAGE ANNUAL TOTAL RETURNS AS OF 1/31/17 (%)

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The Bank of America Merrill Lynch Hybrid Preferred Securities Index is a subset of the Bank of America Merrill Lynch Fixed Rate Preferred Securities Index, including all subordinated securities with a payment deferral feature. The Bank of America Merrill Lynch Fixed Rate Preferred Securities Index tracks the performance of fixed-rate U.S. dollar-denominated preferred securities issued in the U.S. domestic market. Qualifying securities must have an investment-grade rating and the country of risk must also have an investment-grade rating.

It is not possible to invest directly in an index. Index figures do not reflect expenses or sales charges, which would result in lower returns.

The fund's performance at net asset value (NAV) is different from the fund's performance at closing market price because the closing market price is subject to the dynamics of secondary market trading. If a shareholder purchases shares at a time when the market price is at a premium to the NAV or sells shares at a time when the market price is at a discount to the NAV, the shareholder may sustain losses.

The performance data contained within this material represents past performance, which does not guarantee future results.

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       2

PERFORMANCE HIGHLIGHTS OVER THE LAST SIX MONTHS

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Preferred securities and utility common stocks declined

Rising interest rates put pressure on income-producing securities.

Key detractors come from utilities

A few companies were hurt by macroeconomic developments, as indicators of potentially stronger growth put pressure on dividend-producing stocks.

Certain convertible-preferred and energy-related holdings fared well

Energy securities were among the fund's best performers on the late improvement in commodity prices.

PORTFOLIO COMPOSITION AS OF 1/31/17 (%)

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A note about risks

As is the case with all closed-end funds, shares of this fund may trade at a discount or a premium to the fund's net asset value (NAV). An investment in the fund is subject to investment and market risks, including the possible loss of the entire principal invested. There is no guarantee prior distribution levels will be maintained, and distributions may include a substantial tax return of capital. Fixed-income investments are subject to interest-rate risk; their value will normally decline as interest rates rise or if a creditor, grantor, or counterparty is unable or unwilling to make principal, interest, or settlement payments. An issuer of securities held by the fund may default, have its credit rating downgraded, or otherwise perform poorly, which may affect fund performance. Liquidity—the extent to which a security may be sold or a derivative position closed without negatively affecting its market value—may be impaired by reduced trading volume, heightened volatility, rising interest rates, and other market conditions. The fund's use of leverage creates additional risks, including greater volatility of the fund's NAV, market price, and returns. There is no assurance that the fund's leverage strategy will be successful. Focusing on a particular industry or sector may increase the fund's volatility and make it more susceptible to market, economic, and regulatory risks as well as other factors affecting those industries or sectors.

The fund normally will invest at least 25% of its total assets in the industries composing the utilities sector, which includes telecommunications companies, measured at the time of purchase. When the fund's investments focus on one or more sectors of the economy, they are far less diversified than the broad securities markets. This means that the fund may be more volatile than other funds, and the values of its investments may go up and down more rapidly. Because utility companies are capital intensive, they can be hurt by higher interest rates, which would increase the companies' interest burden. They can also be affected by costs in connection with capital construction programs, costs associated with environmental and other regulations, and the effects of economic declines, surplus capacity, and increased competition. In addition, the fund may invest in financial services companies, which can be hurt by economic declines, changes in interest rates, and regulatory and market impacts. The fund's investments in securities of foreign issuers involve special risks, such as political, economic, and currency risks and differences in accounting standards and financial reporting.

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       3

What was the market environment like for preferred securities during the six months ended January 31, 2017?

Income-producing investments—including the preferred securities and utility common stocks that are the main areas of emphasis for the fund—declined during the period amid significant macroeconomic developments that muted demand for such investments. From the outset of the period, better U.S. economic data fanned worries that the U.S. Federal Reserve (Fed) would be induced to raise interest rates in September. This subjected most income-producing investments to a bout of profit taking. Utilities sector securities were among those hit hardest, as investors looked to lock in gains in advance of a rate hike. After the Fed refrained from a rate hike in September, income-producing investments briefly regained some ground.

But in the final months of 2016, preferreds and utility common stocks came under renewed pressure. Initially, data pointing to a strong third-quarter rebound in U.S. economic growth ratcheted up expectations for higher inflation and rising interest rates, resulting in the repricing of income-oriented investments. After the election of Donald Trump, whose proposed policies were viewed as business-friendly measures, stocks of companies that were less dependent on such measures came under further pressure, including high-dividend utility stocks. In early December, the Fed increased short-term rates by 25 basis points. Although this rate hike had, for the most part, been widely anticipated, what surprised the markets was the Fed's summary of economic projections, which showed that the Fed forecast three more interest-rate hikes by the end of 2017, one more than the market was pricing in. This, coupled with year-end tax-loss selling—which investors used to offset investment losses against gains—put additional pressure on preferreds and utilities at year end.

However, January was a strong month for dividend-producing investments. They posted solid gains as value-seeking investors bought preferreds and utility common stocks and tax-loss selling abated.

What's your view on income-producing investments?

We believe that conditions may improve for income-producing investments during the first half of 2017. In our view, interest rates may move gradually higher than they were at the end of 2016, but

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       4

will still remain low relative to historical measures. Although some of the Trump administration's proposed measures are likely to be implemented in 2017, others may not be enacted or felt until 2018 and beyond. Yields on European government debt remain low, suggesting to us that the world economy is not all that healthy. We doubt the Fed will risk upsetting already fragile economic conditions abroad. After the U.S. central bank's September meeting, Fed Chair Janet Yellen noted that economic conditions had strengthened since the first half of the year.

Our longer-term optimism for dividend-paying stocks remains intact. We believe that the aging of the global population should foster ongoing demand for preferred securities and utility common stocks as older people move larger portions of their portfolios into income-producing investments.

What holdings negatively affected performance?

Although the vast majority of preferred securities and utility common stocks suffered price declines during the six-month period, some holdings disappointed even further due to company-related developments. One of our biggest laggards was Teva Pharmaceutical Industries, Ltd., the world's largest maker of generic drugs, which suffered steep security price losses. Political scrutiny of the drug industry's pricing of certain medications hurt Teva, as did news that the company's president and CEO was retiring. Teva was also hurt by revelations that the company would have to pay a substantial fine for alleged bribery of government officials in Russia, Ukraine, and Mexico. We continued to hold the Teva preferred securities the fund owned, given that they carry an attractive 7% coupon and that we believe the company's balance sheet strength will help see it through its current challenges. Holdings in National Grid PLC, an international gas and electric company serving the United Kingdom and the northeastern United States, also performed poorly. The company's common stock price declined significantly on news that it would sell the majority of its stake in its gas distribution networks and cut its dividend payments to shareholders.

SECTOR COMPOSITION AS OF 1/31/17 (%)

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SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       5

"We believe that conditions may improve for income-producing investments during the first half of 2017."

What holdings helped the fund's performance?

Convertible preferred security holdings in Kinder Morgan, Inc. and Great Plains Energy, Inc. performed comparatively well. Both benefited from offering investors an attractive coupon and from positive underlying fundamentals. Additionally, these preferreds were priced throughout much of the period so that investors would stand to gain when the shares are expected to convert to common stocks in 2018.

Some of the portfolio's other energy-related investments were among its best performers for the period. Spectra Energy Corp., a leading U.S. pipeline company, fared particularly well, initially because investors were encouraged that the company's earnings were resilient in the face of turbulent oil and gas prices. Spectra got another late-period boost from the news that it planned to merge in the first quarter of 2017 with Canadian company Enbridge, Inc., creating what the two companies billed as the largest energy infrastructure company in North America. Electric and gas utility CenterPoint Energy, Inc. also performed well, benefiting from improved earnings and good results from the company's growing natural gas and electricity transmission service territory.

Were there any significant changes to the portfolio?

We reduced the fund's holdings in financials from 49.8% to 36.1%. Early in the period, some of the fund's Morgan Stanley and Entergy Corp. preferred issues were called. We were able to replace these with comparably yielding, newly issued convertible preferred securities from utility companies that need to finance acquisitions, including Dominion Resources, Inc. and Great Plains Energy. Toward the end of 2016, we used the proceeds from some preferred securities called to buy other

TOP 10 ISSUERS AS OF 1/31/17 (%)

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Dominion Resources, Inc.	4.8
Kinder Morgan, Inc.	4.4
Great Plains Energy, Inc.	4.1
PPL Capital Funding, Inc.	3.9
JPMorgan Chase & Co.	3.9
Teva Pharmaceutical Industries, Ltd.	3.2
Royal Dutch Shell PLC, ADR	2.9
Barclays Bank PLC	2.9
Wells Fargo & Company	2.8
Duke Energy Corp.	2.7
TOTAL	35.6
As a percentage of total investments.
Cash and cash equivalents are not included.

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       6

preferreds that we felt were attractively valued after having been unduly punished by the broad sell-off of income-producing investments.

Can you tell us about management changes?

We've added Brad Lutz, CFA, to the team. Brad has more than 20 years of investment experience and specializes in fixed-income strategies. Effective August 31, 2017, I will be retiring. Joe and Brad will continue to manage the fund.

MANAGED BY

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	Gregory K. Phelps On the fund since inception Investing since 1981
	Joseph H. Bozoyan, CFA On the fund since 2015 Investing since 1993
	Brad Lutz, CFA On the fund since 2017 Investing since 1992

QUALITY COMPOSITION AS OF 1/31/17 (%)

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The views expressed in this report are exclusively those of Gregory K. Phelps, John Hancock Asset Management, and are subject to change. They are not meant as investment advice. Please note that the holdings discussed in this report may not have been held by the fund for the entire period. Portfolio composition is subject to review in accordance with the fund's investment strategy and may vary in the future. Current and future portfolio holdings are subject to risk.

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       7

 

	As of 1-31-17 (unaudited)
													Shares						Value
	Preferred securities 136.7% (89.9% of Total investments)																		$764,688,117
	(Cost $749,881,543)
	Consumer staples 2.2%																		12,512,500
	Food and staples retailing 2.2%
	Ocean Spray Cranberries, Inc., Series A, 6.250% (S)												143,000						12,512,500
	Energy 6.6%																		37,042,686
	Oil, gas and consumable fuels 6.6%
	Kinder Morgan, Inc., 9.750%												750,916						37,042,686
	Financials 54.9%																		307,003,128
	Banks 34.1%
	Bank of America Corp., 6.500%												115,000						3,007,250
	Bank of America Corp., Depositary Shares, Series D, 6.204%												145,631						3,693,202
	Barclays Bank PLC, Series 3, 7.100%												205,000						5,252,100
	Barclays Bank PLC, Series 5, 8.125% (Z)												740,000						19,092,000
	BB&T Corp., 5.200% (Z)												420,000						10,332,000
	BB&T Corp., 5.625% (Z)												450,000						11,322,000
	Citigroup Capital XIII, 7.409% (P)												15,000						387,300
	Citigroup, Inc., 5.800%												65,000						1,630,850
	Citigroup, Inc., 6.875%												60,000						1,585,200
	Citigroup, Inc. (6.875% to 11-15-23, then 3 month LIBOR + 4.130%) (Z)												410,175						11,406,967
	Citigroup, Inc. (7.125% to 9-30-23, then 3 month LIBOR + 4.040%)												182,773						5,112,161
	First Republic Bank, 7.000% (Z)												95,000						2,624,850
	ING Groep NV, 6.125% (Z)												61,500						1,554,105
	ING Groep NV, 7.200% (L)(Z)												100,000						2,582,000
	JPMorgan Chase & Co., 5.450% (Z)												400,000						10,052,000
	JPMorgan Chase & Co., 5.500% (Z)												61,961						1,544,688
	JPMorgan Chase & Co., 6.100% (Z)												122,000						3,146,380
	JPMorgan Chase & Co., 6.125% (Z)												670,000						17,433,400
	JPMorgan Chase & Co., 6.300% (Z)												25,000						653,750
	Regions Financial Corp., 6.375%												138,164						3,528,709
	Royal Bank of Scotland Group PLC, Series L, 5.750% (Z)												560,000						13,720,000
	Santander Holdings USA, Inc., Series C, 7.300%												365,000						9,417,000
	The PNC Financial Services Group, Inc., 5.375% (Z)												30,000						737,400
	The PNC Financial Services Group, Inc. (6.125% to 5-1-22, then 3 month LIBOR + 4.067%) (Z)												187,000						5,303,320
	U.S. Bancorp (6.000% to 4-15-17, then 3 month LIBOR + 4.861%) (Z)												60,000						1,524,600

SEE NOTES TO FINANCIAL STATEMENTS

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       8

													Shares						Value
	Financials  (continued)
	Banks  (continued)
	U.S. Bancorp (6.500% to 1-15-22, then 3 month LIBOR + 4.468%) (Z)												705,000						$20,621,250
	Wells Fargo & Company, 6.000% (Z)												127,000						3,294,380
	Wells Fargo & Company, 8.000% (L)(Z)												756,000						20,117,160
	Capital markets 7.5%
	Deutsche Bank Contingent Capital Trust II, 6.550%												10,000						245,800
	Deutsche Bank Contingent Capital Trust III, 7.600%												370,000						9,460,900
	Morgan Stanley, 6.625%												80,000						2,102,400
	Morgan Stanley (6.375% to 10-15-24, then 3 month LIBOR + 3.708%)												85,000						2,251,650
	State Street Corp., 5.250% (Z)												155,000						3,799,050
	State Street Corp., 6.000% (Z)												580,600						15,333,646
	The Goldman Sachs Group, Inc., 5.950%												185,100						4,675,626
	The Goldman Sachs Group, Inc., Series B, 6.200% (Z)												160,000						4,104,000
	Consumer finance 4.1%
	Capital One Financial Corp., 6.200%												287,251						7,411,076
	Capital One Financial Corp., 6.700%												54,991						1,494,655
	Navient Corp., 6.000%												305,042						6,588,907
	SLM Corp., Series A, 6.970%												147,391						7,443,246
	Insurance 9.1%
	Aegon NV, 6.375% (Z)												520,000						13,176,800
	Aegon NV, 6.500% (Z)												260,000						6,728,800
	Prudential Financial, Inc., 5.750% (L)(Z)												140,000						3,514,000
	Prudential PLC, 6.500% (L)(Z)												154,500						3,983,010
	Prudential PLC, 6.750%												51,000						1,310,190
	RenaissanceRe Holdings Ltd., Series C, 6.080%												25,000						633,250
	W.R. Berkley Corp., 5.625% (L)(Z)												885,000						21,328,500
	Thrifts and mortgage finance 0.1%
	Federal National Mortgage Association, Series S, 8.250% (I)												80,000						741,600
	Health care 4.9%																		27,161,230
	Pharmaceuticals 4.9%
	Teva Pharmaceutical Industries, Ltd., 7.000%												44,050						27,161,230
	Industrials 2.2%																		12,493,800
	Machinery 2.2%
	Stanley Black & Decker, Inc., 5.750% (L)(Z)												495,000						12,493,800
	Real estate 11.4%																		63,722,678
	Equity real estate investment trusts 11.4%
	Digital Realty Trust, Inc., 7.375%												34,936						957,596

SEE NOTES TO FINANCIAL STATEMENTS

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       9

													Shares						Value
	Real estate  (continued)
	Equity real estate investment trusts  (continued)
	Kimco Realty Corp., 6.000% (Z)												895,000						$22,527,150
	Public Storage, 5.200% (L)(Z)												125,000						3,007,500
	Public Storage, 5.750% (L)(Z)												452,403						11,156,258
	Senior Housing Properties Trust, 5.625% (L)(Z)												835,790						19,758,074
	Ventas Realty LP, 5.450% (L)(Z)												245,000						6,316,100
	Telecommunication services 8.3%																		46,206,024
	Diversified telecommunication services 1.6%
	Qwest Corp., 6.125% (Z)												30,000						737,100
	Qwest Corp., 7.000% (Z)												20,000						503,400
	Qwest Corp., 7.500%												116,654						2,956,012
	Verizon Communications, Inc., 5.900% (Z)												168,000						4,425,120
	Wireless telecommunication services 6.7%
	Telephone & Data Systems, Inc., 6.625% (Z)												233,381						5,836,859
	Telephone & Data Systems, Inc., 6.875%												119,781						3,017,283
	Telephone & Data Systems, Inc., 7.000% (Z)												340,000						8,608,800
	United States Cellular Corp., 6.950% (Z)												795,000						20,121,450
	Utilities 46.2%																		258,546,071
	Electric utilities 31.3%
	Duke Energy Corp., 5.125% (Z)												920,000						23,018,400
	Entergy Louisiana LLC, 5.250% (L)(Z)												241,476						5,889,600
	FPL Group Capital Trust I, 5.875% (Z)												345,000						8,756,100
	Great Plains Energy, Inc., 7.000% (L)(Z)												676,000						34,631,480
	HECO Capital Trust III, 6.500% (Z)												379,850						9,929,279
	Interstate Power & Light Company, 5.100% (Z)												270,000						7,192,800
	NextEra Energy Capital Holdings, Inc., 5.700% (L)(Z)												905,000						22,416,850
	NSTAR Electric Company, 4.780% (L)(Z)												15,143						1,506,729
	PPL Capital Funding, Inc., 5.900% (Z)												1,312,439						32,902,846
	SCE Trust I, 5.625% (L)(Z)												240,000						5,935,200
	SCE Trust II, 5.100% (Z)												549,000						13,165,020
	SCE Trust III (5.750% to 3-15-24, then 3 month LIBOR + 2.990%) (Z)												20,000						523,200
	The Southern Company, 6.250% (Z)												351,399						9,220,710
	Independent power and renewable electricity producers 0.6%
	AES Trust III, 6.750%												68,296						3,483,096
	Multi-utilities 14.3%
	BGE Capital Trust II, 6.200% (Z)												710,000						18,353,500
	Dominion Resources, Inc., 6.750% (Z)												700,667						35,558,850
	DTE Energy Company, 5.250% (Z)												528,107						13,054,805
	DTE Energy Company, 6.000%												96,175						2,436,113
	DTE Energy Company, 6.500%												73,100						3,876,493

SEE NOTES TO FINANCIAL STATEMENTS

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       10

													Shares						Value
	Utilities  (continued)
	Multi-utilities  (continued)
	Integrys Holding, Inc. (6.000% to 8-1-23, then 3 month LIBOR + 3.220%) (Z)												260,000						$6,695,000
	Common stocks 11.6% (7.6% of Total investments)																		$64,901,105
	(Cost $56,946,391)
	Energy 10.5%																		58,570,305
	Oil, gas and consumable fuels 10.5%
	BP PLC, ADR (L)(Z)												601,000						21,623,980
	Royal Dutch Shell PLC, ADR, Class A (L)(Z)												448,024						24,368,025
	Spectra Energy Corp.												302,000						12,578,300
	Utilities 1.1%																		6,330,800
	Multi-utilities 1.1%
	CenterPoint Energy, Inc. (Z)												130,000						3,407,300
	National Grid PLC, ADR												50,000						2,923,500
							Rate (%)			Maturity date			Par value^						Value
	Corporate bonds 2.3% (1.5% of Total investments)																		$12,675,500
	(Cost $12,940,556)
	Energy 1.4%																		7,513,000
	Oil, gas and consumable fuels 1.4%
	Energy Transfer Partners LP (P)(Z)						3.903			11-01-66						8,800,000			7,513,000
	Utilities 0.9%																		5,162,500
	Multi-utilities 0.9%
	Dominion Resources, Inc. (5.750% to 10-1-24, then 3 month LIBOR + 3.057%) (L)(Z)						5.750			10-01-54						5,000,000			5,162,500
							Yield* (%)			Maturity date			Par value^						Value
	Short-term investments 1.5% (1.0% of Total investments)																		$8,424,000
	(Cost $8,424,000)
	U.S. Government Agency 1.5%																		8,145,000
	Federal Home Loan Bank Discount Note						0.400			02-01-17						8,145,000			8,145,000
													Par value^						Value
	Repurchase agreement 0.0%																		279,000
	Repurchase Agreement with State Street Corp. dated 1-31-17 at 0.100% to be repurchased at $279,001 on 2-1-17, collateralized by $285,000 U.S. Treasury Notes, 1.250% due 10-31-19 (valued at $284,654, including interest)												279,000						279,000

SEE NOTES TO FINANCIAL STATEMENTS

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       11

													Par value^						Value
	Repurchase agreement  (continued)
	Total investments (Cost $828,192,490)† 152.1%																		$850,688,722
	Other assets and liabilities, net (52.1%)																		($291,486,002	)
	Total net assets 100.0%																		$559,202,720

The percentage shown for each investment category is the total value of the category as a percentage of the net assets of the fund unless otherwise indicated.

^All par values are denominated in U.S. dollars unless otherwise indicated.

Key to Security Abbreviations and Legend

ADR

American Depositary Receipts

LIBOR

London Interbank Offered Rate

(I)

Non-income producing security.

(L)

A portion of this security is on loan as of 1-31-17, and is a component of the fund'sleverage under the Credit Facility Agreement.

(P)

Variable rate obligation. The coupon rate shown represents the rate at period end.

(S)

These securities are exempt from registration under Rule 144A of the Securities Act of 1933. Such securities may be resold, normally to qualified institutional buyers, in transactions exempt from registration. Rule 144A securities amounted to $12,512,500 or 2.2% of the fund's net assets as of 1-31-17.

(Z)

All or a portion of this security is pledged as collateral pursuant to the Credit Facility Agreement. Total collateral value at 1-31-17 was $623,504,378. A portion of the securities pledged as collateral were loaned pursuant to the Credit Facility Agreement. The value of securities on loan amounted to $199,229,742.

*

Yield represents either the annualized yield at the date of purchase, the stated coupon rate or, for floating rate securities, the rate at period end.

†

At 1-31-17, the aggregate cost of investment securities for federal income tax purposes was $828,193,094. Net unrealized appreciation aggregated to $22,495,628, of which $38,075,156 related to appreciated investment securities and $15,579,528 related to depreciated investment securities.

SEE NOTES TO FINANCIAL STATEMENTS

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       12

	Assets
	Investments, at value (Cost $828,192,490)						$850,688,722
	Cash						356
	Dividends and interest receivable						1,421,877
	Swap contracts, at value						69,312
	Other receivables and prepaid expenses						72,972
	Total assets						852,253,239
	Liabilities
	Committed facility agreement						292,500,000
	Payable for investments purchased						416,050
	Interest payable						24,045
	Payable to affiliates
	Accounting and legal services fees						19,971
	Trustees' fees						986
	Other liabilities and accrued expenses						89,467
	Total liabilities						293,050,519
	Net assets						$559,202,720
	Net assets consist of
	Paid-in capital						$607,898,081
	Accumulated distributions in excess of net investment income						(614,466								)
	Accumulated net realized gain (loss) on investments, futures contracts and swap agreements						(70,649,318								)
	Net unrealized appreciation (depreciation) on investments, translation of assets and liabilities in foreign currencies and swap agreements						22,568,423
	Net assets						$559,202,720
	Net asset value per share
	Based on 25,994,476 shares of beneficial interest outstanding — unlimited number of shares authorized with no par value						$21.51

SEE NOTES TO FINANCIAL STATEMENTS

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       13

	Investment income
	Dividends									$26,609,757
	Interest									394,478
	Less foreign taxes withheld									(312,313											)
	Total investment income									26,691,922
	Expenses
	Investment management fees									3,252,375
	Accounting and legal services fees									92,299
	Transfer agent fees									15,959
	Trustees' fees									22,849
	Printing and postage									86,474
	Professional fees									29,835
	Custodian fees									34,727
	Stock exchange listing fees									12,696
	Interest expense									1,949,599
	Other									7,921
	Total expenses									5,504,734
	Less expense reductions									(32,899											)
	Net expenses									5,471,835
	Net investment income									21,220,087
	Realized and unrealized gain (loss)
	Net realized gain (loss) on
	Investments									4,808,280
	Futures contracts									1,887,665
	Swap contracts									(417,168											)
										6,278,777
	Change in net unrealized appreciation (depreciation) of
	Investments and translation of assets and liabilities in foreign currencies									(42,396,760											)
	Futures contracts									2,293,186
	Swap contracts									508,640
										(39,594,934											)
	Net realized and unrealized loss									(33,316,157											)
	Decrease in net assets from operations									($12,096,070											)

SEE NOTES TO FINANCIAL STATEMENTS

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       14

										Six months ended 1-31-17												Year ended 7-31-16
										(unaudited)
	Increase (decrease) in net assets
	From operations
	Net investment income									$21,220,087												$41,573,397
	Net realized gain (loss)									6,278,777												(608,876				)
	Change in net unrealized appreciation (depreciation)									(39,594,934				)								30,465,527
	Increase (decrease) in net assets resulting from operations									(12,096,070				)								71,430,048
	Distributions to shareholders
	From net investment income									(21,834,553				)								(40,325,104				)
	From tax return of capital									—												(3,328,819				)
	Total distributions									(21,834,553				)								(43,653,923				)
	From fund share transactions
	Issued pursuant to Dividend Reinvestment Plan									128,372												122,512
	Total increase (decrease)									(33,802,251				)								27,898,637
	Net assets
	Beginning of period									593,004,971												565,106,334
	End of period									$559,202,720												$593,004,971
	Accumulated distributions in excess of net investment income									($614,466				)								—
	Share activity
	Shares outstanding
	Beginning of period									25,988,795												25,983,314
	Issued pursuant to Dividend Reinvestment Plan									5,681												5,481
	End of period									25,994,476												25,988,795

SEE NOTES TO FINANCIAL STATEMENTS

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       15

	Cash flows from operating activities
	Net decrease in net assets from operations			($12,096,070)
	Adjustments to reconcile net increase in net assets from operations to net cash provided by operating activities:
	Long-term investments purchased			(117,044,210)
	Long-term investments sold			112,723,947
	Decrease in short term investments			1,449,000
	Net amortization of premium (discount)			109,400
	Decrease in dividends and interest receivable			1,123,875
	Decrease in cash segregated at custodian for derivative contracts			450,000
	Decrease in cash held at broker for futures contracts			864,000
	Increase in other receivables and prepaid expenses			(43,091)
	Decrease in payable for investments purchased			(2,547,861)
	Decrease in unrealized depreciation of swap contracts			(508,640)
	Decrease in payable for futures variation margin			(310,000)
	Decrease in payable to affiliates			(23,239)
	Decrease in interest payable			(14,904)
	Decrease in other liabilities and accrued expenses			(17,555)
	Net change in unrealized (appreciation) depreciation on investments			42,399,639
	Net realized gain on investments			(4,808,280)
	Net cash provided by operating activities			$21,706,011
	Cash flows from financing activities
	Distributions to shareholders			($21,706,217)
	Net cash used in financing activities			($21,706,217		)
	Net decrease in cash			($206		)
	Cash at beginning of period			$562
	Cash at end of period			$356
	Supplemental disclosure of cash flow information
	Cash paid for interest			$1,964,503
	Noncash financing activities not included herein consists of reinvestment distributions			$128,372

SEE NOTES TO FINANCIAL STATEMENTS

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       16

	COMMON SHARES Period Ended																					1-31-171																		7-31-16																					7-31-15																		7-31-14															7-31-13												7-31-12
	Per share operating performance
	Net asset value, beginning of period																					$22.82																		$21.75																					$21.31																		$20.51															$22.03												$20.70
	Net investment income2																					0.82																		1.60																					1.65																		1.67															1.74												1.74
	Net realized and unrealized gain (loss) on investments																					(1.29										)								1.15																					0.47																		0.81															(1.58				)								1.27
	Total from investment operations																					(0.47										)								2.75																					2.12																		2.48															0.16												3.01
	Less distributions to common shareholders
	From net investment income																					(0.84										)								(1.55													)								(1.68										)								(1.68							)								(1.68				)								(1.68							)
	From tax return of capital																					—																		(0.13													)								—																		—															—												—
	Total distributions																					(0.84										)								(1.68													)								(1.68										)								(1.68							)								(1.68				)								(1.68							)
	Net asset value, end of period																					$21.51																		$22.82																					$21.75																		$21.31															$20.51												$22.03
	Per share market value, end of period																					$21.00																		$23.22																					$19.76																		$19.93															$20.05												$23.40
	Total return at net asset value (%)3,4																					(1.95										) 5								13.66																					10.72																		13.27															0.52												15.25
	Total return at market value (%)3																					(5.92										) 5								27.30																					7.55																		8.36															(7.49				)								26.58
	Ratios and supplemental data
	Net assets applicable to common shares, end of period (in millions)																					$559																		$593																					$565																		$554															$533												$572
	Ratios (as a percentage of average net assets):
				Expenses before reductions																		1.92										6								1.79																					1.69																		1.76															1.68												1.74
				Expenses including reductions7																		1.91										6								1.78																					1.68																		1.76															1.68												1.74
				Net investment income																		7.41										6								7.33																					7.58																		8.30															7.88												8.40
	Portfolio turnover (%)																					13																		14																					11																		6															21												18
	Senior securities
	Total debt outstanding end of period (in millions)																					$293																		$293																					$293																		$293															$293												$283
	Asset coverage per $1,000 of debt8																					$2,912																		$3,027																					$2,932																		$2,893															$2,822												$3,020

	1			Six months ended 1-31-17. Unaudited.
	2			Based on average daily shares outstanding.
	3			Total return based on net asset value reflects changes in the fund's net asset value during each period. Total return based on market value reflects changes in market value. Each figure assumes that distributions from income, capital gains and tax return of capital, if any, were reinvested. These figures will differ depending upon the level of any discount from or premium to net asset value at which the fund's shares traded during the period.
	4			Total returns would have been lower had certain expenses not been reduced during the applicable periods.
	5			Not annualized.
	6			Annualized.
	7			Expenses including reductions excluding interest expense were 1.23% (annualized), 1.23%, 1.22%, 1.27%,1.22% and 1.24% for the periods ended 1-31-17, 7-31-16, 7-31-15, 7-31-14, 7-31-13 and 7-31-12, respectively.
	8			Asset coverage equals the total net assets plus borrowings divided by the borrowings of the fund outstanding at period end (Note 7). As debt outstanding changes, the level of invested assets may change accordingly. Asset coverage ratio provides a measure of leverage.

SEE NOTES TO FINANCIAL STATEMENTS

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       17

Note 1 — Organization

John Hancock Preferred Income Fund (the fund) is a closed-end management investment company organized as a Massachusetts business trust and registered under the Investment Company Act of 1940, as amended (the 1940 Act).

Note 2 — Significant accounting policies

The financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (US GAAP), which require management to make certain estimates and assumptions as of the date of the financial statements. Actual results could differ from those estimates and those differences could be significant. The fund qualifies as an investment company under Topic 946 of Accounting Standards Codification of US GAAP.

Events or transactions occurring after the end of the fiscal period through the date that the financial statements were issued have been evaluated in the preparation of the financial statements. The following summarizes the significant accounting policies of the fund:

Security valuation. Investments are stated at value as of the scheduled close of regular trading on the New York Stock Exchange (NYSE), normally at 4:00 p.m., Eastern Time. In case of emergency or other disruption resulting in the NYSE not opening for trading or the NYSE closing at a time other than the regularly scheduled close, the net asset value (NAV) may be determined as of the regularly scheduled close of the NYSE pursuant to the fund's Valuation Policies and Procedures.

In order to value the securities, the fund uses the following valuation techniques: Equity securities held by the fund are typically valued at the last sale price or official closing price on the exchange or principal market where the security trades. In the event there were no sales during the day or closing prices are not available, the securities are valued using the last available bid price. Debt obligations are valued based on the evaluated prices provided by an independent pricing vendor or from broker-dealers. Independent pricing vendors utilize matrix pricing which takes into account factors such as institutional-size trading in similar groups of securities, yield, quality, coupon rate, maturity, type of issue, trading characteristics and other market data, as well as broker supplied prices. Swaps are valued using evaluated prices obtained from an independent pricing vendor.

In certain instances, the Pricing Committee may determine to value equity securities using prices obtained from another exchange or market if trading on the exchange or market on which prices are typically obtained did not open for trading as scheduled, or if trading closed earlier than scheduled, and trading occurred as normal on another exchange or market.

Other portfolio securities and assets, for which reliable market quotations are not readily available, are valued at fair value as determined in good faith by the fund's Pricing Committee following procedures established by the Board of Trustees. The frequency with which these fair valuation procedures are used cannot be predicted and fair value of securities may differ significantly from the value that would have been used had a ready market for such securities existed.

The fund uses a three-tier hierarchy to prioritize the pricing assumptions, referred to as inputs, used in valuation techniques to measure fair value. Level 1 includes securities valued using quoted prices in active markets for identical securities. Level 2 includes securities valued using other significant observable inputs. Observable inputs may include quoted prices for similar securities, interest rates, prepayment speeds and credit risk. Prices for securities valued using these inputs are received from independent pricing vendors and brokers and are based on an evaluation of the inputs described. Level 3 includes securities valued using significant unobservable inputs when market prices are not readily available or reliable, including the fund's own assumptions in determining the fair value of investments. Factors used in determining value may include market or issuer specific events or trends, changes in interest rates and credit quality. The inputs or methodology used for valuing securities are not necessarily an indication of the risks associated with investing in those securities. Changes in valuation techniques and related inputs may result in transfers into or out of an assigned level within the disclosure hierarchy.

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       18

The following is a summary of the values by input classification of the fund's investments as of January 31, 2017, by major security category or type:

		Total value at 1-31-17	Level 1 quoted price	Level 2 significant observable inputs	Level 3 significant unobservable inputs
Preferred securities
	Consumer staples	$12,512,500	—	$12,512,500	—
	Energy	37,042,686	$37,042,686	—	—
	Financials	307,003,128	307,003,128	—	—
	Health care	27,161,230	27,161,230	—	—
	Industrials	12,493,800	12,493,800	—	—
	Real estate	63,722,678	63,722,678	—	—
	Telecommunication services	46,206,024	41,780,904	4,425,120	—
	Utilities	258,546,071	251,851,071	6,695,000	—
Common stocks		64,901,105	64,901,105	—	—
Corporate bonds		12,675,500	—	12,675,500	—
Short-term investments		8,424,000	—	8,424,000	—
Total investments in securities		$850,688,722	$805,956,602	$44,732,120	—
Other financial instruments:
Interest rate swaps		$69,312	—	$69,312	—

Repurchase agreements. The fund may enter into repurchase agreements. When the fund enters into a repurchase agreement, it receives collateral that is held in a segregated account by the fund's custodian. The collateral amount is marked-to-market and monitored on a daily basis to ensure that the collateral held is in an amount not less than the principal amount of the repurchase agreement plus any accrued interest. Collateral received by the fund for repurchase agreements is disclosed in the Fund's investments as part of the caption related to the repurchase agreement.

Repurchase agreements are typically governed by the terms and conditions of the Master Repurchase Agreement and/or Global Master Repurchase Agreement (collectively, MRA). Upon an event of default, the non-defaulting party may close out all transactions traded under the MRA and net amounts owed. Absent an event of default, assets and liabilities resulting from repurchase agreements are not offset in the Statement of assets and liabilities. In the event of a default by the counterparty, realization of the collateral proceeds could be delayed, during which time the collateral value may decline or the counterparty may have insufficient assets to pay back claims resulting from close-out of the transactions.

Security transactions and related investment income. Investment security transactions are accounted for on a trade date plus one basis for daily NAV calculations. However, for financial reporting purposes, investment transactions are reported on trade date. Interest income is accrued as earned. Interest income includes coupon interest and amortization/accretion of premiums/discounts on debt securities. Debt obligations may be placed in a non-accrual status and related interest income may be reduced by stopping current accruals and writing off interest receivable when the collection of all or a portion of interest has become doubtful. Dividend income is recorded on the ex-date, except for dividends of foreign securities where the dividend may not be known until after the ex-date. In those cases, dividend income, net of withholding taxes, is recorded when the fund becomes aware of the dividends. Distributions received on securities that represent a tax return of capital or capital gain are recorded as a reduction of cost of investments and/or as a realized gain if amounts are estimable. Foreign taxes are provided for based on the fund's understanding of the tax rules and rates that exist in the foreign markets in which it invests. Gains and losses on securities sold are determined on the basis of identified cost and may include proceeds from litigation.

Real estate investment trusts. The fund may invest in real estate investment trusts (REITs). Distributions from REITs may be recorded as income and subsequently characterized by the REIT at the end of the fiscal year as a reduction of cost of

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       19

investments and/or as a realized gain. As a result, the fund will estimate the components of distributions from these securities. Such estimates are revised when the actual components of the distributions are known.

Foreign taxes. The fund may be subject to withholding tax on income and/or capital gains or repatriation taxes imposed by certain countries in which the fund invests. Taxes are accrued based upon investment income, realized gains or unrealized appreciation.

Overdrafts. Pursuant to the custodian agreement, the fund's custodian may, in its discretion, advance funds to the fund to make properly authorized payments. When such payments result in an overdraft, the fund is obligated to repay the custodian for any overdraft, including any costs or expenses associated with the overdraft. The custodian may have a lien, security interest or security entitlement in any fund property that is not otherwise segregated or pledged, to the maximum extent permitted by law, to the extent of any overdraft.

Expenses. Within the John Hancock group of funds complex, expenses that are directly attributable to an individual fund are allocated to such fund. Expenses that are not readily attributable to a specific fund are allocated among all funds in an equitable manner, taking into consideration, among other things, the nature and type of expense and the fund's relative net assets. Expense estimates are accrued in the period to which they relate and adjustments are made when actual amounts are known.

Federal income taxes. The fund intends to continue to qualify as a regulated investment company by complying with the applicable provisions of the Internal Revenue Code and will not be subject to federal income tax on taxable income that is distributed to shareholders. Therefore, no federal income tax provision is required.

Under the Regulated Investment Company Modernization Act of 2010, the fund is permitted to carry forward capital losses incurred in taxable years beginning after December 22, 2010 for an unlimited period. Any losses incurred during those taxable years will be required to be utilized prior to the losses incurred in pre-enactment taxable years. As a result of this ordering rule, pre-enactment capital loss carryforwards may be more likely to expire unused. Additionally, post-enactment capital losses that are carried forward will retain their character as either short-term or long-term capital losses rather than being considered all short-term as under previous law.

For federal income tax purposes, as of July 31, 2016, the fund has a capital loss carryforward of $79,601,784 available to offset future net realized capital gains. The following table details the capital loss carryforward available:

Capital loss carryforward expiring at July 31			No Expiration Date
2017	2018	2019	Short-Term	Long-Term
$53,099,790	$11,734,215	$2,278,715	$2,576,127	$9,912,937

As of July 31, 2016, the fund had no uncertain tax positions that would require financial statement recognition, derecognition or disclosure. The fund's federal tax returns are subject to examination by the Internal Revenue Service for a period of three years.

Distribution of income and gains. Distributions to shareholders from net investment income and net realized gains, if any, are recorded on the ex-date. The fund generally declares and pays dividends monthly and capital gain distributions, if any, annually.

Such distributions, on a tax basis, are determined in conformity with income tax regulations, which may differ from US GAAP.

Capital accounts within the financial statements are adjusted for permanent book-tax differences. These adjustments have no impact on net assets or the results of operations. Temporary book-tax differences, if any, will reverse in a subsequent period. Book-tax differences are primarily attributable to derivative transactions and REITs.

Statement of cash flows. Information on financial transactions that have been settled through the receipt and disbursement of cash is presented in the Statement of cash flows. The cash amount shown in the Statement of cash flows is the amount included in the fund's Statement of assets and liabilities and represents the cash on hand at the fund's custodian and does not include any short-term investments.

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       20

Note 3 — Derivative Instruments

The fund may invest in derivatives in order to meet its investment objective. Derivatives include a variety of different instruments that may be traded in the over-the-counter (OTC) market, on a regulated exchange or through a clearing facility. The risks in using derivatives vary depending upon the structure of the instruments, including the use of leverage, optionality, the liquidity or lack of liquidity of the contract, the creditworthiness of the counterparty or clearing organization and the volatility of the position. Some derivatives involve risks that are potentially greater than the risks associated with investing directly in the referenced securities or other referenced underlying instrument. Specifically, the fund is exposed to the risk that the counterparty to an OTC derivatives contract will be unable or unwilling to make timely settlement payments or otherwise honor its obligations. OTC derivatives transactions typically can only be closed out with the other party to the transaction.

Swaps are typically traded through the OTC market. Derivative counterparty risk is managed through an ongoing evaluation of the creditworthiness of all potential counterparties and, if applicable, designated clearing organizations. The fund attempts to reduce its exposure to counterparty risk for derivatives traded in the OTC market, whenever possible, by entering into an International Swaps and Derivatives Association (ISDA) Master Agreement with each of its OTC counterparties. The ISDA gives each party to the agreement the right to terminate all transactions traded under the agreement if there is certain deterioration in the credit quality or contractual default of the other party, as defined in the ISDA. Upon an event of default or a termination of the ISDA, the non-defaulting party has the right to close out all transactions and to net amounts owed.

As defined by the ISDA, the fund may have collateral agreements with certain counterparties to mitigate counterparty risk on OTC derivatives. Subject to established minimum levels, collateral for OTC transactions is generally determined based on the net aggregate unrealized gain or loss on contracts with a particular counterparty. Collateral pledged to the fund is held in a segregated account by a third-party agent or held by the custodian bank for the benefit of the fund and can be in the form of cash or debt securities issued by the U.S. government or related agencies; collateral posted by the fund for OTC transactions is held in a segregated account at the fund's custodian and is noted in the accompanying Fund's investments, or if cash is posted, on the Statement of assets and liabilities. The fund's maximum risk of loss due to counterparty risk is equal to the asset value of outstanding contracts offset by collateral received.

Futures. A futures contract is a contractual agreement to buy or sell a particular currency or financial instrument at a pre-determined price in the future. Risks related to the use of futures contracts include possible illiquidity of the futures markets, contract prices that can be highly volatile and imperfectly correlated to movements in the underlying financial instrument and potential losses in excess of the amounts recognized on the Statement of assets and liabilities. Use of long futures contracts subjects the fund to the risk of loss up to the notional value of the futures contracts. Use of short futures contracts subjects the fund to unlimited risk of loss.

Upon entering into a futures contract, the fund is required to deposit initial margin with the broker in the form of cash or securities. The amount of required margin is generally based on a percentage of the contract value; this amount is the initial margin for the trade. The margin deposit must then be maintained at the established level over the life of the contract. Futures margin receivable / payable is included on the Statement of assets and liabilities. Futures contracts are marked-to-market daily and an appropriate payable or receivable for the change in value (variation margin) and unrealized gain or loss is recorded by the fund. When the contract is closed, the fund records a realized gain or loss equal to the difference between the value of the contract at the time it was opened and the value at the time it was closed.

During the six months ended January 31, 2017, the fund used futures contracts to manage against anticipated interest rate changes. The fund held futures contracts with notional values ranging up to $85.2 million, as measured at each quarter end. At January 31, 2017, the fund held no open futures contracts.

Interest rate swaps. Interest rate swaps represent an agreement between the fund and a counterparty to exchange cash flows based on the difference between two interest rates applied to a notional amount. The payment flows are usually netted against each other, with the difference being paid by one party to the other. The fund settles accrued net interest receivable or payable under the swap contracts at specified, future intervals. Swap agreements are privately negotiated in the OTC market or may be executed on a registered commodities exchange (centrally cleared swaps). Swaps are marked-to-market daily and the change in value is recorded as unrealized appreciation/depreciation of swap contracts. A termination payment by the

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       21

counterparty or the fund is recorded as realized gain or loss, as well as the net periodic payments received or paid by the fund. The value of the swap will typically impose collateral posting obligations on the party that is considered out-of-the-money on the swap.

Entering into swap agreements involves, to varying degrees, elements of credit, market and documentation risk that may amount to values that are in excess of the amounts recognized on the Statement of assets and liabilities. Such risks involve the possibility that there will be no liquid market for the swap, or that a counterparty may default on its obligation or delay payment under the swap terms. The counterparty may disagree or contest the terms of the swap. Market risks may also accompany the swap, including interest rate risk. The fund may also suffer losses if it is unable to terminate or assign outstanding swaps or reduce its exposure through offsetting transactions.

During the six months ended January 31, 2017, the fund used interest rate swaps to manage against anticipated interest rate changes. The fund held interest rate swaps with total USD notional amounts ranging from $68.0 million to $136.0 million, as measured at each quarter end. The following table summarizes the interest rate swap contracts held as of January 31, 2017:

Counterparty	USD notional amount	Payments made by fund	Payments received by fund	Maturity date	Market value
Morgan Stanley Capital Services	$68,000,000	Fixed 0.8750%	3 Month LIBOR (a)	Jul 2017	$69,312

^(a) At 1-31-17, 3-month LIBOR was 1.03456%

Fair value of derivative instruments by risk category

The table below summarizes the fair value of derivatives held by the fund at January 31, 2017 by risk category:

Risk	Statement of assets and liabilities location	Financial instruments location	Asset derivatives fair value	Liabilities derivative fair value
Interest rate	Swap contracts, at value	Interest rate swaps	$69,312	—

For financial reporting purposes, the fund does not offset OTC derivative assets or liabilities that are subject to master netting arrangements, as defined by the ISDAs, in the Statement of assets and liabilities. In the event of default by the counterparty or a termination of the agreement, the ISDA allows an offset of amounts across the various transactions between the fund and the applicable counterparty.

Effect of derivative instruments on the Statement of operations

The table below summarizes the net realized gain (loss) included in the net increase (decrease) in net assets from operations, classified by derivative instrument and risk category, for the six months ended January 31, 2017:

Risk

Statement of operations location

Future contracts

Swap contracts

Total

Interest rate

Net realized gain (loss)

$1,887,665

($417,168

)

$1,470,497

The table below summarizes the net change in unrealized appreciation (depreciation) included in the net increase (decrease) in net assets from operations, classified by derivative instrument and risk category, for the six months ended January 31, 2017:

Risk	Statement of operations location	Future contracts	Swap contracts	Total
Interest rate	Change in unrealized appreciation (depreciation)	$2,293,186	$508,640	$2,801,826

Note 4 — Guarantees and indemnifications

Under the fund's organizational documents, its Officers and Trustees are indemnified against certain liabilities arising out of the performance of their duties to the fund. Additionally, in the normal course of business, the fund enters into contracts with service providers that contain general indemnification clauses. The fund's maximum exposure under these arrangements is

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       22

unknown, as this would involve future claims that may be made against the fund that have not yet occurred. The risk of material loss from such claims is considered remote.

Note 5 — Fees and transactions with affiliates

John Hancock Advisers, LLC (the Advisor) serves as investment advisor for the fund. The Advisor is an indirect, wholly owned subsidiary of Manulife Financial Corporation (MFC).

Management fee. The fund has an investment management agreement with the Advisor under which the fund pays a daily management fee to the Advisor, equivalent on an annual basis, to 0.75% of the fund's average daily managed assets including any assets attributable to the Credit Facility Agreement (see Note 7) (collectively, managed assets). The Advisor has a subadvisory agreement with John Hancock Asset Management a division of Manulife Asset Management (US) LLC, an indirectly owned subsidiary of MFC and an affiliate of the Advisor. The fund is not responsible for payment of the subadvisory fees.

The Advisor has contractually agreed to waive a portion of its management fee and/or reimburse expenses for certain funds of the John Hancock group of funds complex, including the fund (the participating portfolios). This waiver is based upon aggregate net assets of all the participating portfolios. The amount of the reimbursement is calculated daily and allocated among all the participating portfolios in proportion to the daily net assets of each fund. During the six months ended January 31, 2017, this waiver amounted to 0.01% of the fund's average net assets (on an annualized basis). This arrangement may be amended or terminated at any time by the Advisor upon notice to the fund and with the approval of the Board of Trustees.

The expense reductions described above amounted to $32,899 for the six months ended January 31, 2017.

Expenses waived or reimbursed in the current fiscal period are not subject to recapture in future fiscal periods.

The investment management fees incurred for the six months ended January 31, 2017 were equivalent to a net annual effective rate of 0.74% of the fund's average daily managed assets.

Accounting and legal services. Pursuant to a service agreement, the fund reimburses the Advisor for all expenses associated with providing the administrative, financial, legal, accounting and recordkeeping services to the fund, including the preparation of all tax returns, periodic reports to shareholders and regulatory reports, among other services. These accounting and legal services fees incurred for the six months ended January 31, 2017 amounted to an annual rate of 0.02% of the fund's average daily managed assets.

Trustee expenses. The fund compensates each Trustee who is not an employee of the Advisor or its affiliates. These Trustees receive from the fund and the other John Hancock closed-end funds an annual retainer. In addition, Trustee out-of-pocket expenses are allocated to each fund based on its net assets relative to other funds within the John Hancock group of funds complex.

Note 6 — Leverage risk

The fund utilizes a Credit Facility Agreement (CFA) to increase its assets available for investment. When the fund leverages its assets, common shareholders bear the fees associated with the CFA and have potential to benefit or be disadvantaged from the use of leverage. The Advisor's fee is also increased in dollar terms from the use of leverage. Consequently, the fund and the Advisor may have differing interests in determining whether to leverage the fund's assets. Leverage creates risks that may adversely affect the return for the holders of common shares, including:

•	the likelihood of greater volatility of NAV and market price of common shares;
•	fluctuations in the interest rate paid for the use of the credit facility;
•	increased operating costs, which may reduce the fund's total return;
•	the potential for a decline in the value of an investment acquired through leverage, while the fund's obligations under such leverage remains fixed; and
•	the fund is more likely to have to sell securities in a volatile market in order to meet asset coverage or other debt compliance requirements.

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       23

To the extent the income or capital appreciation derived from securities purchased with funds received from leverage exceeds the cost of leverage, the fund's return will be greater than if leverage had not been used, conversely, returns would be lower if the cost of the leverage exceeds the income or capital appreciation derived.

In addition to the risks created by the fund's use of leverage, the fund is subject to the risk that it would be unable to timely, or at all, obtain replacement financing if the CFA is terminated. Were this to happen, the fund would be required to de-leverage, selling securities at a potentially inopportune time and incurring tax consequences. Further, the fund's ability to generate income from the use of leverage would be adversely affected.

Note 7 — Credit facility agreement

The fund has entered into a CFA with a subsidiary of BNP Paribas (BNP) that allows it to borrow up to $292,500,000 (maximum facility amount) and to invest the borrowings in accordance with its investment practices.

The fund pledges a portion of its assets as collateral to secure borrowings under the CFA. Such pledged assets are held in a special custody account with the fund's custodian. The amount of assets required to be pledged by the fund is determined in accordance with the CFA. The fund retains the benefits of ownership of assets pledged to secure borrowings under the CFA. Interest charged is at the rate of one month LIBOR (London Interbank Offered Rate) plus 0.70% and is payable monthly. As of January 31, 2017, the fund had borrowings of $292,500,000 at an interest rate of 1.48%, which are reflected in the CFA payable on the Statement of assets and liabilities. During the six months ended January 31, 2017, the average borrowings under the CFA and the effective average interest rate were $292,500,000 and 1.32%, respectively.

The fund is required to pay a commitment fee equal to 0.60% on any unused portion of the maximum facility amount, only for days on which the aggregate outstanding amount of the loans under the CFA is less than 80% of the maximum facility amount. For the six months ended January 31, 2017, there were no commitment fees incurred by the fund.

The fund may terminate the CFA with 30 days' notice. If certain asset coverage and collateral requirements, minimum net assets or other covenants are not met, the CFA could be deemed in default and result in termination. Absent a default or facility termination event, BNP generally is required to provide the fund with 360 days' notice prior to terminating or amending the CFA.

The fund has an agreement with BNP that allows BNP to borrow a portion of the pledged collateral (Lent Securities) in an amount not to exceed the lesser of: (i) outstanding borrowings owed by the fund to BNP or (ii) 331/3% of the fund's total assets. The fund can designate any security within the pledged collateral as ineligible to be a Lent Security and can recall any of the Lent Securities. The fund also has the right to apply and set-off an amount equal to 100% of the then-current fair market value of such Lent Securities against the current borrowings under the CFA in the event that BNP fails to timely return the Lent Securities and in certain other circumstances. In such circumstances, however, the fund may not be able to obtain replacement financing required to purchase replacement securities and, consequently, the fund's income generating potential may decrease. Even if the fund is able to obtain replacement financing, it might not be able to purchase replacement securities at favorable prices. Income earned from Lent Securities of $60,581 for the six months ended January 31, 2017 is recorded as a component of interest income on the Statement of operations.

Note 8 — Purchase and sale of securities

Purchases and sales of securities, other than short-term investments, amounted to $117,044,210 and $112,723,947, respectively, for the six months ended January 31, 2017.

Note 9 — Industry or sector risk

The fund may invest a large percentage of its assets in one or more particular industries or sectors of the economy. If a large percentage of the fund's assets are economically tied to a single or small number of industries or sectors of the economy, the fund will be less diversified than a more broadly diversified fund, and it may cause the fund to underperform if that industry or sector underperforms. In addition, focusing on a particular industry or sector may make the fund's NAV more volatile. Further, a fund that invests in particular industries or sectors is particularly susceptible to the impact of market, economic, regulatory and other factors affecting those industries or sectors.

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       24

Note 10 — New rule issuance

In October 2016, the Securities and Exchange Commission (SEC) issued Final Rule Release No.33-10231, Investment Company Reporting Modernization (the Release). The Release calls for the adoption of new rules and forms as well as amendments to its rules and forms to modernize the reporting and disclosure of information by registered investment companies. The SEC is adopting amendments to Regulation S-X, which will require standardized, enhanced disclosure about derivatives in investment company financial statements, as well as other amendments. Management is in the process of reviewing the impact to the financial statements.

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       25

ADDITIONAL INFORMATION

---

Unaudited

Investment objective and principal investment strategies

The fund is a closed-end, diversified management investment company, common shares of which were initially offered to the public on August 27, 2002 and are publicly traded on the New York Stock Exchange (the NYSE). The fund's primary investment objective is to provide a high level of current income consistent with preservation of capital. The fund's secondary investment objective is to provide growth of capital to the extent consistent with its primary investment objective. The fund seeks to achieve its investment objectives by investing in securities that, in the opinion of the Advisor, may be undervalued relative to similar securities in the marketplace. The fund's principal investment strategies include, but are not limited to, the following: Under normal market conditions, the fund invests at least 80% of its assets (net assets plus borrowings for investment purposes) in preferred stocks and other preferred securities, including convertible preferred securities. In addition, the fund normally invests 25% or more of its total assets in the industries composing the utilities sector.

Dividends and distributions

During the six months ended January 31, 2017, distributions from net investment income totaling $0.8400 per share were paid to shareholders. The dates of payments and the amounts per share were as follows:

Payment Date	Distributions
August 31, 2016	$0.1400
September 30, 2016	0.1400
October 31, 2016	0.1400
November 30, 2016	0.1400
December 30, 2016	0.1400
January 31, 2017	0.1400
Total	$0.8400

Shareholder meeting

---

The fund held its Annual Meeting of Shareholders on January 24, 2017. The following proposal was considered by the shareholders:

Proposal: To elect five (5) Trustees (James R. Boyle, William H. Cunningham, Grace K. Fey, Hassell H. McClellan and Gregory A. Russo) to serve for a three-year term ending at the 2020 Annual Meeting of Shareholders. Each Trustee was re-elected by the fund's shareholders and the votes cast with respect to each Trustee are set forth below.

	Total votes for the nominee	Total votes withheld from the nominee
Independent Trustees
William H. Cunningham	22,368,878.534	737,778.000
Grace K. Fey	22,384,536.534	722,120.000
Hassell H. McClellan	22,348,799.534	757,857.000
Gregory A. Russo	22,361,542.834	745,113.700
Non-Independent Trustees
James R. Boyle	22,373,313.534	733,343.000,

Trustees whose term of office continued after the Annual Meeting of Shareholders because they were not up for election are: Charles L. Bardelis, Peter S. Burgess, Craig Bromley, Theron F. Hoffman, Deborah C. Jackson, James M. Oates, Steven R. Pruchansky, and Warren A. Thomson.

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       26

Trustees Hassell H. McClellan, Chairperson# Steven R. Pruchansky, Vice Chairperson Charles L. Bardelis* James R. Boyle† Craig Bromley† Peter S. Burgess* William H. Cunningham Grace K. Fey Theron S. Hoffman* Deborah C. Jackson James M. Oates Gregory A. Russo Warren A. Thomson† Officers Andrew G. Arnott President John J. Danello Senior Vice President, Secretary, and Chief Legal Officer Francis V. Knox, Jr. Chief Compliance Officer Charles A. Rizzo Chief Financial Officer Salvatore Schiavone Treasurer

Investment advisor John Hancock Advisers, LLC Subadvisor John Hancock Asset Management a division of Manulife Asset Management (US) LLC Custodian State Street Bank and Trust Company Transfer agent Computershare Shareowner Services, LLC Legal counsel K&L Gates LLP Stock symbol Listed New York Stock Exchange: HPI

*Member of the Audit Committee
†Non-Independent Trustee
^#Effective 1-1-17

The fund's proxy voting policies and procedures, as well as the fund proxy voting record for the most recent twelve-month period ended June 30, are available free of charge on the Securities and Exchange Commission (SEC) website at sec.gov or on our website.

The fund's complete list of portfolio holdings, for the first and third fiscal quarters, is filed with the SEC on Form N-Q. The fund's Form N-Q is available on our website and the SEC's website, sec.gov, and can be reviewed and copied (for a fee) at the SEC's Public Reference Room in Washington, DC. Call 800-SEC-0330 to receive information on the operation of the SEC's Public Reference Room.

We make this information on your fund, as well as monthly portfolio holdings, and other fund details available on our website at jhinvestments.com or by calling 800-852-0218.

	You can also contact us:
		800-852-0218 jhinvestments.com	Regular mail: Computershare P.O. Box 30170 College Station, TX 77842-3170

SEMIANNUAL REPORT   |   JOHN HANCOCK PREFERRED INCOME FUND       27

 

DOMESTIC EQUITY FUNDS Balanced Blue Chip Growth Classic Value Disciplined Value Disciplined Value Mid Cap Equity Income Fundamental All Cap Core Fundamental Large Cap Core Fundamental Large Cap Value New Opportunities Small Cap Value Small Company Strategic Growth U.S. Global Leaders Growth U.S. Growth Value Equity GLOBAL AND INTERNATIONAL EQUITY FUNDS Disciplined Value International Emerging Markets Emerging Markets Equity Global Equity Global Shareholder Yield Greater China Opportunities International Growth International Small Company International Value Equity		INCOME FUNDS Bond California Tax-Free Income Emerging Markets Debt Floating Rate Income Global Income Government Income High Yield High Yield Municipal Bond Income Investment Grade Bond Money Market Short Duration Credit Opportunities Spectrum Income Strategic Income Opportunities Tax-Free Bond ALTERNATIVE AND SPECIALTY FUNDS Absolute Return Currency Alternative Asset Allocation Enduring Assets Financial Industries Global Absolute Return Strategies Global Conservative Absolute Return Global Focused Strategies Global Real Estate Natural Resources Redwood Regional Bank Seaport Technical Opportunities

The fund's investment objectives, risks, charges, and expenses are included in the prospectus and should be considered carefully before investing. For a prospectus, contact your financial professional, call John Hancock Investments at 800-852-0218, or visit the fund's website at jhinvestments.com. Please read the prospectus carefully before investing or sending money.

ASSET ALLOCATION Income Allocation Fund Multimanager Lifestyle Portfolios Multi-Index Preservation Portfolios Multimanager Lifetime Portfolios Multi-Index Lifetime Portfolios EXCHANGE-TRADED FUNDS John Hancock Multifactor Consumer Discretionary ETF John Hancock Multifactor Consumer Staples ETF John Hancock Multifactor Developed International ETF John Hancock Multifactor Energy ETF John Hancock Multifactor Financials ETF John Hancock Multifactor Healthcare ETF John Hancock Multifactor Industrials ETF John Hancock Multifactor Large Cap ETF John Hancock Multifactor Materials ETF John Hancock Multifactor Mid Cap ETF John Hancock Multifactor Technology ETF John Hancock Multifactor Utilities ETF		ENVIRONMENTAL, SOCIAL, AND GOVERNANCE FUNDS ESG All Cap Core ESG Core Bond ESG International Equity ESG Large Cap Core CLOSED-END FUNDS Financial Opportunities Hedged Equity & Income Income Securities Trust Investors Trust Preferred Income Preferred Income II Preferred Income III Premium Dividend Tax-Advantaged Dividend Income Tax-Advantaged Global Shareholder Yield

John Hancock Multifactor ETF shares are bought and sold at market price (not NAV), and are not individually redeemed
from the fund. Brokerage commissions will reduce returns.

John Hancock ETFs are distributed by Foreside Fund Services, LLC, and are subadvised by Dimensional Fund Advisors LP.
Foreside is not affiliated with John Hancock Funds, LLC or Dimensional Fund Advisors LP.

Dimensional Fund Advisors LP receives compensation from John Hancock in connection with licensing rights to the
John Hancock Dimensional indexes. Dimensional Fund Advisors LP does not sponsor, endorse, or sell, and makes no
representation as to the advisability of investing in, John Hancock Multifactor ETFs.

John Hancock Investments

A trusted brand

John Hancock Investments is a premier asset manager representing one of
America's most trusted brands, with a heritage of financial stewardship dating
back to 1862. Helping our shareholders pursue their financial goals is at the
core of everything we do. It's why we support the role of professional financial
advice and operate with the highest standards of conduct and integrity.

A better way to invest

We serve investors globally through a unique multimanager approach:
We search the world to find proven portfolio teams with specialized
expertise for every strategy we offer, then we apply robust investment
oversight to ensure they continue to meet our uncompromising standards
and serve the best interests of our shareholders.

Results for investors

Our unique approach to asset management enables us to provide a diverse set
of investments backed by some of the world's best managers, along with strong
risk-adjusted returns across asset classes.

	John Hancock Advisers, LLC 601 Congress Street n Boston, MA 02210-2805 800-852-0218 n jhinvestments.com
	MF348586	P8SA 1/17 3/17