OMB APPROVAL OMB Number: 3235-0578 Expires: May 31, 2007 Estimated average burden hours per response..... 21.09 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM N-Q CERTIFIED SHAREHOLDER REPORT OF REGISTERED MANAGEMENT INVESTMENT COMPANIES Investment Company Act file number 811-21043 Pioneer High Income Trust (Exact name of registrant as specified in charter) 60 State Street, Boston, MA 02109 (Address of principal executive offices) (ZIP code) Dorothy E. Bourassa, Pioneer Investment Management, Inc., 60 State Street, Boston, MA 02109 (Name and address of agent for service) Registrant's telephone number, including area code: (617) 742-7825 Date of fiscal year end: March 31 Date of reporting period: June 30, 2006 Form N-Q is to be used by management investment companies, other than small business investment companies registered on Form N-5 (239.24 and 274.5 of this chapter), to file reports with the Commission, not later than 60 days after close of the first and third fiscal quarters, pursuant to Rule 30b1-5under the Investment Company Act of 1940 (17 CFR 270.30b-5). The Commission may use the information provided on Form N-Q in its regulatory, disclosure review, inspection, and policymaking roles. A registrant is required to disclose the information specified by Form N-Q, and the Commission will make this information public. A registrant is not required to respond to the collection of information contained in Form N-Q unless the Form displays a currently valid Office of Management and Budget ("OMB") control number. Please direct comments concerning the accuracy of the information collection burden estimate and any suggestions for reducing the burden to Secretary, Securities and Exchange Commission, 450 Fifth Street, NW, Washington, DC 20549-0609. The OMB has reviewed this collection of information under the clearance requirements of 44 U.S.C. ss. 3507. ITEM 1. Schedule of Investments. Pioneer High Income Trust SCHEDULE OF INVESTMENTS 6/30/06 (unaudited) Principal S&P/Moody's Amount Ratings USD ($) (unaudited) Value COLLATERIZED MORTGAGE OBLIGATIONS - 1.2% of Net Assets Diversified Financials - 1.2% 425,000 BB/Ba3 DB Master Finance LLC, 8.285%, 6/20/31 (144 $426,637 4,860,000 NR/Ba2 Tower 2004-2A F, 6.376%, 12/15/14 (144A) 4,773,589 TOTAL COLLATERIZED MORTGAGE OBLIGATIONS $5,200,226 (Cost $5,284,991) CORPORATE BONDS & NOTES - 117.4% of Net Assets Energy - 11.0% Oil & Gas Drilling - 1.1% 4,400,000 NR/NR DDI Holding AS, 9.3%, 1/19/12 (144A) $4,521,000 Oil & Gas Equipment & Services - 1.5% 2,100,000 (a)CCC+/B3 Pipe Acquisition Finance Plc, 11.67%, 12/15 $2,068,500 2,380,000 NR/B1 SemGroup L.P., 8.75%, 11/15/15 (144A) 2,368,100 2,000,000 NR/NR Sevan Marine ASA, 9.75%, 1/31/11 (144A) 2,010,000 $6,446,600 Oil & Gas Exploration & Production - 7.7% 9,534,000 (i)B-/B3 Baytex Energy, Ltd., 9.625%, 7/15/10 $9,843,855 4,080,000 B-/B3 Clayton William Energy, 7.75%, 8/1/13 3,753,600 5,000,000 B+/B2 Energy Partners, Ltd., 8.75%, 8/1/10 4,812,500 1,250,000 B/B3 Hilcorp Energy I, LP/Hilcorp Finance Co., 9 1,259,375 4,500,000 BBB-/Ba1 Methanex Corp., 8.75%, 8/15/12 4,831,875 5,300,000 CCC+/Caa1PetroQuest Energy, Inc., 10.375%, 5/15/12 5,485,500 3,135,000 B-/Caa1 Stone Energy Corp., 6.75%, 12/15/14 3,146,756 $33,133,461 Oil & Gas Storage & Transportation - 0.7% 820,000 B-/B2 Targa Resources, Inc., 8.5%, 11/1/13 (144A) $791,300 2,188,000 B-/B3 Transmontaigne, Inc., 9.125%, 6/1/10 2,330,220 $3,121,520 Total Energy $47,222,581 Materials - 26.1% Commodity Chemicals - 5.1% 4,635,000 BB-/Ba3 ARCO Chemical Co., 9.8%, 2/1/20 $5,446,125 2,920,000 (a)B-/B3 Aventine Renewable Energy, 11.329%, 12/15/1 3,076,950 5,000,000 B+/Ba3 Invista, 9.25%, 5/1/12 (144A) 5,250,000 3,300,000 B+/B1 Tronox Worldwide LLC/Tronox Finance Corp., 3,399,000 4,280,000 B-/B3 VeraSun Energy Corp., 9.875%, 12/15/12 (144 4,515,400 $21,687,475 Diversified Chemicals - 7.0% 3,200,000 B-/B2 Basell Finance Co., 8.1%, 3/15/27 (144A) $2,896,000 810,000 BB/NR Braskem SA, 9.375%, 6/1/15 (144A) 814,050 2,200,000 BB/NR Braskem SA, 11.75%, 1/22/14 2,453,000 6,060,000 (b)B/Caa2 Crystal US Holdings, 10.5%, 10/1/14 4,741,950 7,870,000 B/B3 Huntsman International LLC, 10.125%, 7/1/09 10,213,983 2,000,000 B-/B2 Ineos Group Holdings Plc., 8.5%, 2/15/16 (1 1,872,500 1,190,000 B-/B2 Nell AF S.a.r.l., 8.375%, 8/15/15 (144A) 1,536,819 500,000 B-/B2 Nell AF S.a.r.l., 8.375%, 8/15/15 (144A) 480,625 3,904,000 B-/Caa1 Rhodia SA, 9.25%, 6/1/11 5,191,556 $30,200,483 Specialty Chemicals - 1.6% 1,000,000 B/NR Ferro Corp., 7.625%, 5/1/13 $982,500 5,970,000 (i)B+/B3 PolyOne Corp., 8.875%, 5/1/12 5,992,388 $6,974,888 Construction Materials - 1.5% 2,225,000 CCC+/Caa1RMCC Acquisition Co., 9.5%, 11/1/12 (144A) $2,314,000 4,185,000 B-/B3 U.S. Concrete, Inc., 8.375%, 4/1/14 4,226,850 $6,540,850 Metal & Glass Containers - 1.9% 4,020,000 BB-/B1 Greif Bros. Corp., 8.875%, 8/1/12 $4,231,050 3,985,000 B-/B2 Vitro Envases, 10.75%, 7/23/11 (144A) 4,104,550 $8,335,600 Paper Packaging - 2.3% 1,685,000 (i)CCC+/Caa2Graham Packaging Co., L.P., 9.875%, 10/15/1 $1,668,150 5,540,000 (i)B-/B3 Graphic Packaging International, Inc., 9.5% 5,484,600 2,000,000 B-/B3 MDP Acquisitions Plc, 10.125%, 10/1/12 2,774,688 $9,927,438 Aluminum - 1.1% 1,440,000 B/B3 Aleris International, Inc., 9.0%, 11/15/14 $1,465,200 1,200,000 BB/Ba3 Asia Aluminum Holdings, Ltd., 8.0%, 12/23/1 1,125,000 2,180,000 B-/B3 Indalex Holding Corp., 11.5%, 2/1/14 (144A) 2,223,600 $4,813,800 Diversified Metals & Mining - 2.5% 3,300,000 B-/B3 American Rock Salt Co., LLC, 9.5%, 3/15/14 $3,341,250 4,600,000 B+/B1 Freeport-McMoRan Copper & Gold, Inc., 10.12 4,881,750 2,599,000 B-/Caa1 OM Group, Inc., 9.25%, 12/15/11 2,676,970 $10,899,970 Steel - 1.5% 2,900,000 BB/Ba2 CSN Islands VIII Corp., 9.75%, 12/16/13 (14 $3,103,000 630,000 BB/Ba2 CSN Islands IX Corp., 10.5%, 1/15/15 (144A) 693,000 2,485,000 B-/B3 Edgen Acquisition Corp., 9.875%, 2/1/11 2,422,875 $6,218,875 Forest Products - 0.3% 1,645,000 B-/B3 Mandra Forestry Holdings, Ltd., 12.0%, 5/15 $1,266,650 Pioneer High Income Trust SCHEDULE OF INVESTMENTS 6/30/06 (unaudited) (continued) Principal S&P/Moody's Amount Ratings USD ($) (unaudited) Value Paper Products - 1.3% 5,450,000 B-/B2 Exopack Holding Corp., 11.25%, 2/1/14 (144A $5,504,500 Total Materials $112,370,529 Capital Goods - 10.9% Building Products - 0.7% 2,885,000 (a)B/B3 Builders FirstSource, Inc., 9.42%, 2/15/12 $2,957,125 Construction & Engineering - 3.3% 1,250,000 B+/Ba3 Dycom Industries, Inc., 8.125%, 10/15/15 $1,253,125 27,300,000(b)NR/NR Kvaerner ASA, 0.0%, 10/30/11 4,332,393 8,897,000 (b)NR/NR Kvaerner ASA, 0.0%, 10/30/11 8,563,362 $14,148,880 Heavy Electrical Equipment - 2.0% 4,790,000 CCC+/B3 Altra Industrial Motion, 9.0%, 12/1/11 $4,813,950 3,975,000 B/B2 Hawk Corp., 8.75%, 11/1/14 3,994,875 $8,808,825 Construction & Farm Machinery & Heavy Truck - 3.2% 2,000,000 B-/B3 Accuride Corp., 8.5%, 2/1/15 $1,920,000 5,000,000 B+/Ba3 Commercial Vehicle Group, Inc., 8.0%, 7/1/1 4,787,500 1,800,000 B+/B1 Greenbrier Companies, Inc., 8.375%, 5/15/15 1,838,250 5,475,000 CCC+/Caa1Stanadyne Corp., 10.0%, 8/15/14 5,119,125 $13,664,875 Industrial Machinery - 0.3% 1,217,000 B+/B2 Manitowac Co., Inc., 10.5%, 8/1/12 $1,320,445 Trading Companies & Distributors - 1.4% 2,845,000 B/B3 Interline Brands, Inc., 8.125%, 6/15/14 $2,837,888 2,500,000 CCC+/Caa1Ray Acquisition SCA, 9.375%, 3/16/15 (144A) 3,340,494 $6,178,382 Total Capital Goods $47,078,532 Commercial Services & Supplies - 8.8% Diversified Commercial & Professional Services - 4.7% 3,500,000 CCC+/Caa1Allied Security Escrow, 11.375%, 7/15/11 $3,395,000 1,850,000 B/B2 Brickman Group, Ltd., Series B, 11.75%, 12/ 1,988,750 4,455,000 B-/Caa1 Cardtronics, Inc., 9.25%, 8/15/13 (144A) 4,388,175 2,980,000 CCC+/B3 Cornell Companies, Inc., 10.75%, 7/1/12 3,169,975 1,500,000 (a)B-/Caa1 FS Funding AS, 9.489%, 5/15/16 (144A) 1,870,037 2,970,000 CCC+/Caa1Park-Ohio Industries, Inc., 8.375%, 11/15/1 2,613,600 2,745,000 (i)B/Caa1 United Rentals North America, Inc., 7.75%, 2,607,750 $20,033,287 Human Resource & Employment Services - 0.6% 2,700,000 B-/B3 Knowledge Learning Corp., Inc., 7.75%, 2/1/ $2,470,500 Environmental & Facilities Services - 3.5% 4,088,000 B+/B1 Clean Harbors, Inc., 11.25%, 7/15/12 $4,599,000 5,020,000 CCC+/Caa1Hydrochem Industrial Services, Inc., 9.25%, 4,844,300 5,800,000 CCC/Caa2 Waste Services, Inc., 9.5%, 4/15/14 5,858,000 $15,301,300 Total Commercial Services & Supplies $37,805,087 Transportation - 9.4% Airlines - 3.3% 1,063,394 CCC+/B3 American Airlines, Inc., 7.379%, 11/23/17 $962,371 2,065,000 (i)CCC+/Caa2AMR Corp., 9.0%, 8/1/12 2,039,188 2,440,000 CCC+/Caa2AMR Corp., 9.8%, 10/1/21 2,275,300 3,200,000 CCC+/Caa2AMR Corp., 10.2%, 3/15/20 3,000,000 1,127,990 B+/B2 Continental Airlines, Inc., Series B, 8.499 1,107,336 5,000,000 B/B3 Continental Airlines, Inc., Series D, 7.568 4,987,306 $14,371,501 Marine - 5.4% 860,000 BB+/NR CMA CGM SA, 7.25%, 2/1/13 (144A) $786,900 3,899,000 (b)CCC+/Caa2H-Lines Finance Holding, 0.0%, 4/1/13 3,343,392 8,000,000 BBB-/Ba1 Seabulk International, Inc., 9.5%, 8/15/13 8,840,000 6,470,000 B/B1 Ship Finance International, Ltd., 8.5%, 12/ 6,146,500 1,060,000 BB-/Ba3 Stena AB, 7.0%, 12/1/16 975,200 2,900,000 B-/B3 Trailer Bridge, Inc., 9.25%, 11/15/11 2,972,500 $23,064,492 Railroads - 0.7% 2,250,000 B-/B3 Grupo Transportacion Ferroviaria Mexicana, SA de CV, 9.375%, 5/1/12 $2,396,250 400,000 B-/B3 Grupo Transportacion Ferroviaria Mexicana, SA de CV, 10.25%, 6/15/07 412,000 $2,808,250 Total Transportation $40,244,243 Automobiles & Components - 2.6% Auto Parts & Equipment - 1.2% 3,590,000 B-/Caa1 Cooper-Standard Automotive, Inc., 8.375%, 1 $2,831,612 2,000,000 B-/B3 UGS Corp., 10.0%, 6/1/12 2,150,000 $4,981,612 Pioneer High Income Trust SCHEDULE OF INVESTMENTS 6/30/06 (unaudited) (continued) Principal S&P/Moody's Amount Ratings USD ($) (unaudited) Value Tires & Rubber - 1.4% 6,510,000 (i)B-/B3 Goodyear Tire & Rubber Co., 9.0%, 7/1/15 $6,217,050 Total Automobiles & Components $11,198,662 Consumer Durable & Apparel - 1.0% Homebuilding - 1.0% 1,100,000 (i)B+/Ba3 WCI Communities, Inc., 6.625%, 3/15/15 $913,000 3,200,000 B/B2 William Lyon Homes, Inc., 7.5%, 2/15/14 2,656,000 700,000 B/B2 William Lyon Homes, Inc., 7.625%, 12/15/12 581,000 Total Consumer Durable & Apparel $4,150,000 Consumer Services - 3.2% Casinos & Gaming - 2.1% 4,500,000 B/B2 Little Traverse Bay Bands of Odawa Indians, $4,443,750 1,700,000 B/B3 Pokagon Gaming Authority, 10.375%, 6/15/14 1,757,375 3,050,000 (i)B-/Caa1 Trump Entertainment Resorts, Inc., 8.5%, 6/ 2,931,813 $9,132,938 Hotels, Resorts & Cruise Lines - 1.1% 2,435,000 B+/B1 Galaxy Entertainment Finance Co., Ltd., 9.8 $2,532,400 1,980,000 (a)B/B3 HRP Myrtle Beach Operations LLC, 9.818%, 4/ 1,960,200 $4,492,600 Total Consumer Services $13,625,538 Media - 4.3% Broadcasting & Cable TV - 1.8% 2,170,000 BB-/B1 Cablemas SA de CV, 9.375%, 11/15/15 (144A) $2,235,100 3,750,000 B-/B2 Kabel Deutschland GMBH, 10.75%, 7/1/14 (144 5,298,439 $7,533,539 Movies & Entertainment - 0.7% 3,000,000 B-/B3 LodgeNet Entertainment Corp., 9.5%, 6/15/13 $3,195,000 Publishing - 1.8% 4,835,000 B/B1 Sheridan Acquisition Corp., 10.25%, 8/15/11 $4,913,569 3,700,000 (b)B-/Caa2 Visant Holding Corp., 0.0%, 12/1/13 2,904,500 $7,818,069 Total Media $18,546,608 Retailing - 3.6% Distributors - 1.1% 4,735,000 B-/Caa1 Intcomex, Inc., 11.75%, 1/15/11 (144A) $4,699,487 Department Stores - 0.9% 3,800,000 BBB-/Baa3J.C. Penney Co., Inc., 8.125%, 4/1/27 $3,926,772 Specialty Stores - 1.6% 1,545,000 (c)CCC+/Caa2AAC Group Holding Corp., 12.75%, 10/1/12 (1 $1,545,000 1,980,000 CCC+/B3 Hines Nurseries, Inc., 10.25%, 10/1/11 1,900,800 3,180,000 CCC/Caa1 Nutro Products, Inc., 10.75%, 4/15/14 (144A 3,271,425 $6,717,225 Total Retailing $15,343,484 Food & Staples Retailing - 1.5% Drug Retail - 0.7% 3,350,000 CC/Caa3 Duane Reade, Inc., 9.75%, 8/1/11 $2,696,750 550,000 (a)CCC/Caa1 Duane Reade, Inc., 9.829% 12/15/10 533,500 $3,230,250 Food Distributors - 0.8% 3,380,000 B+/B2 Wornick Co., 10.875%, 7/15/11 $3,405,350 Total Food & Staples Retailing $6,635,600 Food, Beverage & Tobacco - 2.0% Brewers - 1.6% 5,885,000 BBB/Baa3 Cia Brasileira de Bebida, 10.5%, 12/15/11 $6,841,312 Agricultural Products - 0.4% 2,000,000 BB/Ba2 Cosan SA Industria e Comercio, 8.25%, 2/28/ $1,800,000 Total Food, Beverage & Tobacco $8,641,312 Health Care Equipment & Services - 4.4% Health Care Equipment & Services - 1.3% 1,800,000 B-/Caa1 Accellent, Inc., 10.5%, 12/1/13 $1,840,500 3,800,000 CCC+/B3 Hanger Orthopedic Group, Inc., 10.25%, 6/1/ 3,762,000 $5,602,500 Health Care Services - 2.1% 2,160,000 B-/Caa1 AMR HoldCo/Emcare HoldCo, 10.0%, 2/15/15 $2,262,600 2,900,000 (a)CCC+/NR Medical Services Co., 12.568%, 10/15/11 2,537,500 4,055,000 CCC+/B3 Rural/Metro Corp., 9.875%, 3/15/15 4,191,856 $8,991,956 Pioneer High Income Trust SCHEDULE OF INVESTMENTS 6/30/06 (unaudited) (continued) Principal S&P/Moody's Amount Ratings USD ($) (unaudited) Value Managed Health Care - 1.0% 4,400,000 B-/Caa1 Multiplan, Inc., 10.375%, 4/15/16 (144A) $4,455,000 Total Health Care Equipment & Services $19,049,456 Pharmaceuticals & Biotechnology - 1.6% Pharmaceuticals - 1.6% 6,650,000 CCC+/Caa1Warner Chilcott Corp., 8.75%, 2/1/15 $6,849,500 Total Pharmaceuticals & Biotechnology $6,849,500 Diversified Financials - 4.2% Specialized Finance - 3.5% 6,135,000 B+/B3 Dollar Financial Group, 9.75%, 11/15/11 $6,595,125 7,950,000 BBB/Baa3 GATX Financial Corp., 8.875%, 6/1/09 8,485,933 $15,081,058 Consumer Finance - 0.7% 3,000,000 B+/Ba2 Ford Motor Credit Co., 7.875%, 6/15/10 $2,767,476 Total Diversified Financials $17,848,534 Insurance - 2.5% Life & Health Insurance - 1.3% 5,725,000 B-/B2 Presidential Life Corp., 7.875%, 2/15/09 $5,696,375 Multi-Line Insurance - 1.2% 5,300,000 BB+/Ba1 Allmerica Financial Corp., 7.625%, 10/15/25 $5,312,895 Total Insurance $11,009,270 Software & Services - 0.3% Data Processing & Outsourced Services - 0.2% 640,000 CCC+/Caa1iPayment, Inc., 9.75%, 5/15/14 (144A) $636,800 Application Software - 0.1% 500,000 CCC+/Caa1Serena Software, Inc., 10.375%, 3/15/16 (14 $502,500 Total Software & Services $1,139,300 Technology Hardware & Equipment - 3.5% Communications Equipment - 0.7% 2,900,000 B/B1 Lucent Technologies, Inc., 7.25%, 7/15/06 $2,910,875 Electronic Equipment Manufacturers - 0.0% 215,000 B/B2 General Cable Corp., 9.5%, 11/15/10 $227,900 Office Electronics - 2.8% 11,830,000 B+/Ba3 Xerox Capital Trust I, 8.0%, 2/1/27 $11,874,363 Total Technology Hardware & Equipment $15,013,138 Telecommunication Services - 13.7% Integrated Telecommunication Services - 2.7% 7,149,000 B-/B3 Eschelon Operating Co., 8.375%, 3/15/10 $6,791,550 4,025,000 B+/B2 GCI, Inc., 7.25%, 2/15/14 3,884,125 691,000 NR/Baa3 Tele Norte Leste Participacoes SA, 8.0%, 12 718,640 $11,394,315 Wireless Telecommunication Services - 11.0% 5,587,000 (b)A-/Caa1 Alamosa Delaware, Inc., 12.0%, 7/31/09 $5,936,187 1,625,000 CCC+/Caa1Cell C Property, Ltd., 11.0%, 7/1/15 (144A) 1,356,875 2,855,000 (a)CCC+/Caa1Cleveland Unlimited, Inc., 13.579%, 12/15/1 3,004,887 1,500,000 NR/B3 Digicel, Ltd., 9.25%, 9/1/12 (144A) 1,567,500 3,900,000 B-/B3 Horizon PCS, Inc., 11.375%, 7/15/12 4,382,625 3,950,000 B-/B1 Hughes Network Systems, LLC/HNS Finance Cor 3,871,000 2,200,000 (b)B+/B1 Inmarsat Finance II Plc, 0.0%, 11/15/12 1,872,750 5,150,000 B+/B1 Mobifon Holdings BV, 12.5%, 7/31/10 5,832,375 1,975,000 (b)NR/NR Mobile Satellite Venture, 0.0%, 4/1/13 (144 1,086,250 3,230,000 BB-/Ba3 Mobile Telesystems, 9.75%, 1/30/08 (144A) 3,330,938 3,000,000 (a)CCC/Caa2 Rural Cellular Corp., 10.899%, 11/1/12 (144 3,078,750 4,200,000 B-/B2 Stratos Global Corp., 9.875%, 2/15/13 (144A 3,948,000 5,525,000 B-/Caa1 UbiquiTel Operating Co., 9.875%, 3/1/11 6,008,438 3,200,000 (b)B/Caa1 Zeus Special Subsidiary, Ltd., 0.0%, 2/1/15 2,208,000 $47,484,575 Total Telecommunication Services $58,878,890 Utilities - 2.8% Electric Utilities - 2.7% 2,000,000 B+/Ba3 Aes Chivor SA ESP, 9.75%, 12/30/14 (144A) $2,150,000 1,777,500 BBB-/Baa3Empresa Electrica Guacolda SA, 8.625%, 4/30 1,918,806 1,000,000 NR/NR Mirant JPSCo. Finance, Ltd., 11.0%, 7/6/16 1,000,000 6,207,183 NR/NR Ormat Funding Corp., 8.25%, 12/30/20 6,362,363 $11,431,169 Multi-Utilities - 0.1% 700,000 B/B2 Reliant Energy, Inc., 6.75%, 12/15/14 $644,000 Total Utilities $12,075,169 TOTAL CORPORATE BONDS & NOTES (Cost $478,478,867) $504,725,433 Pioneer High Income Trust SCHEDULE OF INVESTMENTS 6/30/06 (unaudited) (continued) Principal S&P/Moody's Amount Ratings USD ($) (unaudited) Value CONVERTIBLE BONDS & NOTES - 0.9% of Net Assets Capital Goods - 0.9% Electrical Components & Equipment - 0.9% 4,000,000 B/B1 SCI Systems, Inc., 3.0%, 3/15/07 $3,870,000 Total Capital Goods $3,870,000 TOTAL CONVERTIBLE BONDS & NOTES (Cost $3,823,015) $3,870,000 MUNICIPAL BONDS - 9.3% of Net Assets Indiana - 3.0% 1,650,000 BBB-/Ba1 East Chicago Industrial Pollution Ctl. Rev. $1,729,249 3,000,000 BBB-/Ba1 East Chicago Industrial Pollution Ctl. Rev. 3,052,650 3,665,000 BBB-/Ba1 Indiana Dev. Fin. Auth. Pollution Ctl. Rev. 3,746,400 4,250,000 BBB-/Ba1 Indiana Dev. Fin. Auth. Rev., 5.75%, 10/1/1 4,376,523 $12,904,822 Massachusetts - 0.2% 1,000,000 (e)AAA/NR Massachusetts Health & Edl. Facs. Rev., RIB $1,044,620 Michigan - 0.4% 3,000,000 (d)NR/NR Wayne Charter County, Spl. Arpt. Facs. Rev. $1,669,890 New Jersey - 2.2% 4,525,000 B/Caa2 New Jersey Economic Dev. Auth. Rev., 7.0%, $4,742,019 4,000,000 BBB/Baa3 Tobacco Settlement Financing Corp., 7.0%, 6 4,535,360 $9,277,379 New York - 0.9% 3,475,000 BB-/Ba2 New York City Ind. Dev. Agcy., British Airw $3,905,170 North Carolina - 1.6% 4,800,000 NR/NR Charlotte, Spl. Facs. Rev., Charlotte/Dougl $4,709,952 2,000,000 NR/NR Charlotte, Spl. Facs. Rev., Charlotte/Dougl 2,140,780 $6,850,732 Texas - 1.0% 3,200,000 (e)AAA/Aa1 San Antonio, TX, Elec. & Gas, RIB, 7.608%, $4,119,552 TOTAL MUNICIPAL BONDS (Cost $31,861,942) $39,772,165 SOVEREIGN DEBT OBLIGATIONS - 2.2% of Net Assets Brazil - 0.8% 4,800,000,(b)BB/Ba1 Banco Nacional de Desenvolimento Bndes, 8.0 $3,407,497 Ecuador - 0.8% 3,515,000 (b)CCC+/Caa1Federal Republic of Ecuador, 9.0%, 8/15/30 $3,400,763 Russia - 0.6% 2,320,000 (b)BBB/Baa2 Russian Federation, 5.0%, 3/31/30 $2,469,176 TOTAL SOVEREIGN DEBT OBLIGATIONS (Cost $6,055,162) $9,277,436 Shares COMMON STOCKS - 0.1% of Net Assets Pharmaceuticals & Biotechnology - 0.1% Pharmaceuticals - 0.1% 17,818 (i) Teva Pharmaceutical Industries Ltd. $562,871 Total Pharmaceuticals & Biotechnology $562,871 TOTAL COMMON STOCKS (Cost $752,276) $562,871 WARRANTS - 0.0% of Net Assets (f) Materials - 0.0% Forest Products - 0.0% 1,645 Mandra Forestry Holdings, Ltd. - CW13, Expi $- Total Materials $- Transportation - 0.0% Trucking - 0.0% 4,525 Atlantic Express Transportation Corp., Expi $- Total Transportation $- TOTAL WARRANTS (Cost $0) $- Pioneer High Income Trust SCHEDULE OF INVESTMENTS 6/30/06 (unaudited) (continued) Principal Amount USD ($) TEMPORARY CASH INVESTMENTS - 7.5% of Net Assets Repurchase Agreement - 0.8% 3,300,000 Lehman Brothers, Inc., 4.55%, dated 6/30/06, repurchase price of $3,300,000 plus accrued interest on 7/3/06 collateralized by $3,471 $3,300,000 Shares Security Lending Collateral - 6.7% 28,836,932 Securities Lending Investment Fund, 5.161% $28,836,932 TOTAL TEMPORARY CASH INVESTMENTS (Cost $32,136,932) $32,136,932 TOTAL INVESTMENTS IN SECURITIES - 138.6% (Cost $558,393,185) (g) (h) $595,545,063 OTHER ASSETS AND LIABILITIES - (3.4)% $(14,556,701) PREFERRED SHARES AT REDEMPTION VALUE, INCLUDING DIVIDENDS PAYABLE - (35.2)% $(151,147,723) NET ASSETS APPLICABLE TO COMMON SHAREOWNERS $429,840,639 Pioneer High Income Trust SCHEDULE OF INVESTMENTS 6/30/06 (unaudited) (continued) NR Security not rated by S&P or Moody's. (144A) Security is exempt from registration under Rule 144A of the Securities Act of 1933. Such securities may be resold normally to qualified institutional buyers in a transaction exempt from registration. At June 30, 2006, the value of these securities amounted to $156,079,968 or 36.3% of total net assets applicable to common shareowners. (a) Floating rate note. The rate shown is the rate at June 30, 2006. (b) Debt obligation initially issued at one coupon which converts to a higher coupon at a specific date. The rate shown is the rate at June 30, 2006. (c) Represents a pay-in-kind security which may pay interest in additional principal. (d) Security is in default and is non-income producing. (e) The interest rate is subject to change periodically and inversely based upon prevailing market rates. The rate shown is the rate at June 30, 2006. (f) Non-income producing. (g) At June 30, 2006, the net unrealized gain on investments based on cost for federal income tax purposes of $558,905,758 was as follows: Aggregate gross unrealized gain for all investments in which there is an excess of value over tax cost $ 43,354,244 Aggregate gross unrealized loss for all investments in which there is an excess of tax cost over value (6,714,939) Net unrealized gain $ 36,639,305 For financial reporting purposes net unrealized gain was $37,151,878 and cost of investments aggregated $558,393,185. (h) Distribution of investments by country of issue, as a percentage of total holdings, is as follows: United States % Norway 4.3 Canada 3.1 Brazil 2.7 France 1.6 Mexico 1.5 Romania 1.0 Great Britain 1.0 Russia 1.0 Germany 0.9 Cayman Islands 0.6 Ecuador 0.6 Netherlands 0.5 Ireland 0.5 Bermuda 0.4 India 0.4 Colombia 0.4 Luxembourg 0.3 Chile 0.3 Denmark 0.3 South Africa 0.2 China 0.2 Jamaica 0.2 Sweden 0.2 Israel 0.1 % (i) At June 30, 2006, the following securities were out on loan: Principal Amount/ Shares Description Market Value $ 75AAC Group Holding Corp., 12.75%, 10/1/12 (1 $ 755,000 2,044,AMR Corp., 9.0%, 8/1/12 2,018,746 1,45Baytex Energy, Ltd., 9.625%, 7/15/10 1,497,125 6,444,Goodyear Tire & Rubber Co., 9.0%, 7/1/15 6,154,879 1,6Graham Packaging Co., L.P., 9.875%, 10/15/1 1,651,469 5,484Graphic Packaging International, Inc., 9.5% 5,429,160 1Mobile Satellite Venture, 0.0%, 4/1/13 (144 55,000 1,74PolyOne Corp., 8.875%, 5/1/12 1,750,038 Teva Pharmaceutical Industries Ltd. 557,248 $ 3,019Trump Entertainment Resorts, Inc., 8.5%, 6/ 2,902,494 2,7United Rentals North America, Inc., 7.75%, 2,581,673 1,000WCI Communities, Inc., 6.625%, 3/15/15 830,000 2,249Zeus Special Subsidiary, Ltd., 0.0%, 2/1/15 1,551,982 $ 27,734,814 RIB Residual Interest Bonds ITEM 2. CONTROLS AND PROCEDURES. (a) Disclose the conclusions of the registrant's principal executive officer or officers and principal financial officer or officers, or persons performing similar functions, about the effectiveness of the registrant's disclosure controls and procedures (as defined in Rule 30a-3(c) under the Act (17 CFR 270.30a-3(c))) as of a date within 90 days of the filing date of the report that includes the disclosure required by this paragraph, based on their evaluation of these controls and procedures required by Rule 30a-3(b) under the Act (17 CFR270.30a-3(b))) and Rule 13a-15(b) or 15d-15(b) under the Exchange Act (17 CFR240.13a-15(b) or 240.15d-15(b)). The registrant's principal executive officer and principal financial officer have concluded that the registrant's disclosure controls and procedures are effective based on their evaluation of these controls and procedures as of a date within 90 days of the filing date of this report. (b) Disclose any change in the registrant's internal controls over financial reporting (as defined in Rule 30a-3(d) under the Act (17 CFR270.30a-3(d)) that occurred during the registrant's last fiscal quarter that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial reporting. There were no significant changes in the registrant's internal control over financial reporting that occurred during the second fiscal quarter of the period covered by this report that have materially affected, or are reasonably likely to materially affect, the registrant's internal control over financial reporting. The registrant's principal executive officer and principal financial officer, however, voluntarily are reporting the following information: In August of 2006 the registrant's investment adviser enhanced its internal procedures for reporting performance information required to be included in prospectuses. Those enhancements involved additional internal controls over the appropriateness of performance data generated for this purpose. Such enhancements were made following an internal review which identified prospectuses relating to certain classes of shares of a limited number of registrants where, inadvertently, performance information not reflecting the deduction of applicable sales charges was included. Those prospectuses were revised, and the revised prospectuses were distributed to shareholders. ITEM 3. EXHIBITS. (a) A separate certification for each principal executive officer and principal financial officer of the registrant as required by Rule 30a-2 under the Act (17 CFR 270.30a-2). Filed herewith. SIGNATURES [See General Instruction F] Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized. (Registrant) Pioneer High Income Trust By (Signature and Title)* /s/ John F. Cogan, Jr. John F. Cogan, Jr, President Date August 30, 2006 Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated. By (Signature and Title)* /s/ John F. Cogan, Jr. John F. Cogan, Jr., President Date August 30, 2006 By (Signature and Title)* /s/ Vincent Nave Vincent Nave, Treasurer Date August 30, 2006 * Print the name and title of each signing officer under his or her signature.