A bill to amend title 39, United States Code, with respect to the financing of the cost of mailing certain matter free of postage or at reduced rates of postage.

Authorizes a phased increase, over a specified period of time, in postage rates for second-class publications. States that such increases shall take place in two-year steps. Provides that the rates for the first 250,000 pieces of each issue of a second-class publication shall not exceed sixty-six and two-thirds percent of the applicable rates.

Provides that after July 6, 1972, the revenues received from rates for second-class publications shall not exceed fifty percent of the published rate. Requires the Secretary of the Treasury to credit to the Postal Service Fund such sums as may be needed to equal the revenues that would have been received if the publishers of second-class publications were to pay one hundred percent of the applicable rate for such postage. (Amends 39 U.S.C. 3626)