PIONEER AMERICA INCOME TRUST

                   Multiple Class Plan Pursuant to Rule 18f-3
         Class A Shares, Class B Shares, Class C Shares, Class R Shares
                            and Investor Class Shares

                                 August 3, 2004

     Each class of shares of Pioneer America Income Trust, a Massachusetts
business trust (the "Trust") will have the same relative rights and privileges
and be subject to the same sales charges, fees and expenses, except as set forth
below. The Board of Trustees may determine in the future that other distribution
arrangements, allocations of expenses (whether ordinary or extraordinary) or
services to be provided to a class of shares are appropriate and amend this
Multiple Class Plan accordingly without the approval of shareholders of any
class. Except as set forth in the Trust's prospectus(es), shares may be
exchanged only for shares of the same class of another Pioneer mutual fund.

     Article I. Class A Shares

     Class A Shares are sold at net asset value per share and subject to the
initial sales charge schedule or contingent deferred sales charge ("CDSC") and
minimum purchase requirements as set forth in the Trust's prospectus. Class A
Shares shall be entitled to the shareholder services set forth from time to time
in the Trust's prospectus with respect to Class A Shares. Class A Shares are
subject to fees calculated as a stated percentage of the net assets attributable
to Class A Shares under the Trust's Class A Rule 12b-1 Distribution Plan as set
forth in such Distribution Plan. The Class A Shareholders have exclusive voting
rights, if any, with respect to the Trust's Class A Rule 12b-1 Distribution
Plan. Transfer agency fees are allocated to Class A Shares on a per account
basis except to the extent, if any, such an allocation would cause the Trust to
fail to satisfy any requirement necessary to obtain or rely on a private letter
ruling from the Internal Revenue Service ("IRS") relating to the issuance of
multiple classes of shares. Class A Shares shall bear the costs and expenses
associated with conducting a shareholder meeting for matters relating to Class A
Shares.

     The initial purchase date for Class A Shares acquired through (i)
reinvestment of dividends on Class A Shares or (ii) exchange from another
Pioneer mutual fund will be deemed to be the date on which the original Class A
Shares were purchased.

     Article II. Class B Shares

     Class B Shares are sold at net asset value per share without the imposition
of an initial sales charge. However, Class B Shares redeemed within a specified
number of years of purchase will be subject to a CDSC as set forth in the
Trust's prospectus. Class B Shares are sold subject to the minimum purchase
requirements set forth in the Trust's prospectus. Class B Shares shall be
entitled to the shareholder services set forth from time to time in the Trust's
prospectus with respect to Class B Shares. Class B Shares are subject to fees
calculated as a stated percentage of the net assets attributable to Class B
Shares under the Class B Rule 12b-1 Distribution Plan as set forth in such
Distribution Plan. The Class B Shareholders of the Trust have exclusive voting


rights, if any, with respect to the Trust's Class B Rule 12b-1 Distribution
Plan. Transfer agency fees are allocated to Class B Shares on a per account
basis except to the extent, if any, such an allocation would cause the Trust to
fail to satisfy any requirement necessary to obtain or rely on a private letter
ruling from the IRS relating to the issuance of multiple classes of shares.
Class B Shares shall bear the costs and expenses associated with conducting a
shareholder meeting for matters relating to Class B Shares.

     Class B Shares will automatically convert to Class A Shares of the Trust at
the end of a specified number of years after the initial purchase date of Class
B Shares, except as provided in the Trust's prospectus. Such conversion will
occur at the relative net asset value per share of each class without the
imposition of any sales charge, fee or other charge. The conversion of Class B
Shares to Class A Shares may be suspended if it is determined that the
conversion constitutes or is likely to constitute a taxable event under federal
income tax laws.

     The initial purchase date for Class B Shares acquired through (i)
reinvestment of dividends on Class B Shares or (ii) exchange from another
Pioneer mutual fund will be deemed to be the date on which the original Class B
Shares were purchased.

     Article III. Class C Shares

     Class C Shares are sold at net asset value per share without the imposition
of an initial sales charge. Class C Shares redeemed within one (1) year of
purchase will be subject to a CDSC as set forth in the Trust's prospectus. Class
C Shares are sold subject to the minimum purchase requirements set forth in the
Trust's prospectus. Class C Shares shall be entitled to the shareholder services
set forth from time to time in the Trust's prospectus with respect to Class C
Shares. Class C Shares are subject to fees calculated as a stated percentage of
the net assets attributable to Class C Shares under the Class C Rule 12b-1
Distribution Plan as set forth in such Distribution Plan. The Class C
Shareholders of the Trust have exclusive voting rights, if any, with respect to
the Trust's Class C Rule 12b-1 Distribution Plan. Transfer agency fees are
allocated to Class C Shares on a per account basis except to the extent, if any,
such an allocation would cause the Trust to fail to satisfy any requirement
necessary to obtain or rely on a private letter ruling from the IRS relating to
the issuance of multiple classes of shares. Class C Shares shall bear the costs
and expenses associated with conducting a shareholder meeting for matters
relating to Class C Shares.

     The initial purchase date for Class C Shares acquired through (i)
reinvestment of dividends on Class C Shares or (ii) exchange from another
Pioneer mutual fund will be deemed to be the date on which the original Class C
Shares were purchased.

     Article IV. Class R Shares

     Class R Shares are sold at net asset value per share without an initial
sales charge. Class R Shares redeemed within eighteen (18) months of purchase
will be subject to a CDSC as set forth in the Trust's prospectus. Class R Shares
are sold to retirement plans that meet the eligibility requirements for Class R
Shares set forth in the Trust's prospectus. Class R Shares shall be entitled to
the shareholder services set forth from time to time in the Trust's prospectus
with respect to Class R Shares. Class R Shares are subject to fees calculated as
a stated

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percentage of the net assets attributable to Class R Shares under the Class R
Rule 12b-1 Distribution Plan as set forth in such Distribution Plan. The Class R
Shareholders of the Trust have exclusive voting rights, if any, with respect to
the Trust's Class R Rule 12b-1 Distribution Plan. Transfer agency fees are
allocated to Class R Shares on a per account basis except to the extent, if any,
such an allocation would cause the Trust to fail to satisfy any requirement
necessary to obtain or rely on a private letter ruling from the IRS relating to
the issuance of multiple classes of shares. Class R Shares shall bear the costs
and expenses associated with conducting a shareholder meeting for matters
relating to Class R Shares.

     The initial purchase date for Class R Shares acquired through (i)
reinvestment of dividends on Class R Shares or (ii) exchange from another
Pioneer mutual fund will be deemed to be the date on which the original Class R
Shares were purchased.

     Article V. Investor Class

     Investor Class Shares are only issued in connection with reorganizations of
other investment companies, or series thereof, into the Trust or upon
reinvestment of dividends on Investor Class Shares. Investor Class Shares shall
be entitled to the shareholder services set forth from time to time in the
Trust's prospectus with respect to Investor Class Shares. Investor Class Shares
are not subject to a Rule 12b-1 Distribution Plan. Transfer agency fees are
allocated to Investor Class Shares on a per account basis except to the extent,
if any, such an allocation would cause the Trust to fail to satisfy any
requirement necessary to obtain or rely on a private letter ruling from the IRS
relating to the issuance of multiple classes of shares. Investor Class

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Shares shall bear the costs and expenses associated with conducting a
shareholder meeting for matters relating to Investor Class Shares.

     Investor Class Shares will automatically convert to Class A Shares of the
Trust on the second anniversary of the closing of the issuance of such Investor
Class Shares. Such conversion will occur at the relative net asset value per
share of each class without the imposition of any sales charge, fee or other
charge. The conversion of Investor Class Shares to Class A Shares may be
suspended if it is determined that the conversion constitutes or is likely to
constitute a taxable event under federal income tax laws.

     The initial purchase date for Investor Class Shares acquired through (i)
reinvestment of dividends on Class Shares or (ii) exchange from another Pioneer
mutual fund will be deemed to be the date on which the original Investor Class
Shares were issued.

     Article VI. Approval by Board of Trustees

     This Multiple Class Plan shall not take effect until it has been approved
by the vote of a majority (or whatever greater percentage may, from time to
time, be required under Rule 18f-3 under the Act) of (a) all of the Trustees of
the Trust and (b) those of the Trustees who are not "interested persons" (as
such term may be from time to time defined under the Act) of the Trust.

     Article VII. Amendments

     No material amendment to this Multiple Class Plan shall be effective unless
it is approved by the Board of Trustees of the Trust in the same manner as is
provided for approval of this Multiple Class Plan in Article VI.

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