Fitch Affirms Pioneer Closed-End-Fund Preferred Shares at 'AAA'

Fitch Ratings has affirmed the 'AAA' ratings assigned to the auction market preferred shares (AMPS) issued by the following closed-end funds managed by Pioneer Investments Management (Pioneer):

--Pioneer Municipal High Income Trust (NYSE: MHI)

--Pioneer Municipal High Income Advantage Trust (NYSE: MAV)

--Pioneer High Income Trust (NYSE: PHT)

A complete list of rated AMPS series follows at the end of this press release.

As per publicly available information, the Pioneer High Income Trust preferred shares will be paid in full in mid-March.

KEY RATING DRIVERS

The 'AAA' rating affirmations reflect:

-- Sufficient asset coverage provided to the AMPS by the underlying portfolios of assets;

-- The structural protections afforded by mandatory de-leveraging provisions in the event of asset coverage declines;

-- The legal and regulatory parameters that govern the funds' operations;

-- The capabilities of Pioneer as investment advisor.

LEVERAGE

As of Dec.31, 2013, MHI's total assets were approximately $391 million and total leverage was approximately $101 million in AMPS or 26% of total assets.

MAV's total assets were approximately $423 million and total leverage was approximately $150 million, or 35% of total assets.

PHT's total assets were approximately $555 million and total leverage was approximately $151 million, or 27% of total assets.

ASSET COVERAGE

At the time of the rating affirmations, the funds' asset coverage ratios, as calculated in accordance with the Fitch total and net overcollateralization tests (Fitch OC tests) per the 'AAA' rating guidelines outlined in Fitch's applicable criteria, were in excess of 100%, which is the minimum asset coverage amount deemed consistent with an 'AAA' rating. The funds' governing documents require that asset coverage for the AMPS, as calculated in accordance with the Fitch OC tests, be maintained in excess of 100%. Should the asset coverage decline below 100%, the governing documents require the funds to restore compliance within a 40 business day period.

Additionally, as of the same date, the funds' asset coverage ratios for total outstanding AMPS, as calculated in accordance with Pioneer's interpretation of the Investment Company Act of 1940, were in excess of 200%, which is also a minimum asset coverage required by the funds' governing documents.

PIONEER MUNICIPAL HIGH INCOME TRUST (MHI):

MHI is a diversified closed-end management investment company, registered under the Investment Company Act of 1940, as amended, that commenced investment operations in July 2003. The fund seeks to provide a high level of current income exempt from regular federal income tax with a secondary investment objective of capital appreciation. The fund seeks to invest in assets consisting primarily of municipal securities, the interest on which is exempt from regular Federal income tax and preferred securities that are eligible to pay dividends which qualify for the long term capital gains rate for individual investors.

PIONEER MUNICIPAL HIGH INCOME ADVANTAGE TRUST (MAV)

MAV is a diversified closed-end management company, registered under the Investment Company Act of 1940, as amended, that commenced operations in October 2003. The fund seeks to provide a high level of current income exempt from regular federal income tax with a secondary investment objective of capital appreciation. The fund seeks to invest in assets consisting primarily of municipal securities, the interest on which is exempt from regular Federal income tax and preferred securities that are eligible to pay dividends which qualify for the long term capital gains rate for individual investors.

PIONEER HIGH INCOME TRUST (PHT):

PHT is a diversified, closed-end management investment company, registered under the 1940 Act that commenced operations in April 2002. The fund's investment objective is to seek high current income with a secondary objective of capital appreciation. The fund seeks to achieve these objectives by investing at least 80% of its assets below investment-grade (high-yield) debt securities, loans and preferred stock. While the fund may have some exposure to emerging market debt and international high-yield bonds, the focus is on domestic high-yield securities. The fund may also invest up to 50% of the total assets in illiquid securities.

THE ADVISOR

Pioneer acts as the funds' investment advisor and is a wholly owned subsidiary of Pioneer Global Asset Management S.p.A., an investment management arm of UniCredit Banking Group. As of Dec. 31, 2013, Pioneer Global Asset Management S.p.A. had approximately $237 billion of assets under management.

Fitch affirms the following ratings at 'AAA'

Pioneer Municipal High Income Trust (MHI):

--$50,000,000 of auction market preferred shares, series A, with a liquidation preference of $25,000 per share;

--$51,000,000 of auction market preferred shares, series B, with a liquidation preference of $25,000 per share.

Pioneer Municipal High Income Advantage Trust (MAV):

--$75,000,000 of auction market preferred shares, series A, with a liquidation preference of $25,000 per share;

--$75,000,000 of auction market preferred shares, series B, with a liquidation preference of $25,000 per share.

Pioneer High Income Trust (NYSE: PHT):

--$50,500,000 of auction market preferred shares, series M, with a liquidation preference of $25,000 per share;

--$50,500,000 of auction market preferred shares, series W, with a liquidation preference of $25,000 per share;

--$50,000,000 of auction market preferred shares, series TH, with a liquidation preference of $25,000 per share.

RATINGS SENSITIVITY

The assigned ratings may be sensitive to material changes in the leverage composition, portfolio credit quality or market risk of the fund. A material adverse deviation from Fitch guidelines for any key rating driver could cause the rating to be lowered by Fitch.

For additional information about Fitch's rating guidelines applicable to debt and preferred stock issued by closed-end funds, please review the criteria referenced below, which can be found on Fitch's web site at 'www.fitchratings.com'.

To receive complimentary closed-end fund research, opt-in at the following link:

http://pages.fitchemail.fitchratings.com/FAMCEFBlankOptin/

Additional information is available at 'www.fitchratings.com'.

The sources of information used to assess these ratings were the public domain, and Pioneer Investments.

Applicable Criteria and Related Research:

--'Rating Closed-End Fund Debt and Preferred Stock' (Aug. 14, 2013);

--'2014 Outlook: Closed-End Funds' (Jan. 14, 2014).

Applicable Criteria and Related Research:

Rating Closed-End Fund Debt and Preferred Stock

http://www.fitchratings.com/creditdesk/reports/report_frame.cfm?rpt_id=716220

2014 Outlook: Closed-End Funds (Structural Protections Support Rating Stability)

http://www.fitchratings.com/creditdesk/reports/report_frame.cfm?rpt_id=726592

Additional Disclosure

Solicitation Status

http://www.fitchratings.com/gws/en/disclosure/solicitation?pr_id=822397

ALL FITCH CREDIT RATINGS ARE SUBJECT TO CERTAIN LIMITATIONS AND DISCLAIMERS. PLEASE READ THESE LIMITATIONS AND DISCLAIMERS BY FOLLOWING THIS LINK: HTTP://FITCHRATINGS.COM/UNDERSTANDINGCREDITRATINGS. IN ADDITION, RATING DEFINITIONS AND THE TERMS OF USE OF SUCH RATINGS ARE AVAILABLE ON THE AGENCY'S PUBLIC WEBSITE 'WWW.FITCHRATINGS.COM'. PUBLISHED RATINGS, CRITERIA AND METHODOLOGIES ARE AVAILABLE FROM THIS SITE AT ALL TIMES. FITCH'S CODE OF CONDUCT, CONFIDENTIALITY, CONFLICTS OF INTEREST, AFFILIATE FIREWALL, COMPLIANCE AND OTHER RELEVANT POLICIES AND PROCEDURES ARE ALSO AVAILABLE FROM THE 'CODE OF CONDUCT' SECTION OF THIS SITE. FITCH MAY HAVE PROVIDED ANOTHER PERMISSIBLE SERVICE TO THE RATED ENTITY OR ITS RELATED THIRD PARTIES. DETAILS OF THIS SERVICE FOR RATINGS FOR WHICH THE LEAD ANALYST IS BASED IN AN EU-REGISTERED ENTITY CAN BE FOUND ON THE ENTITY SUMMARY PAGE FOR THIS ISSUER ON THE FITCH WEBSITE.