It does so by mechanisms such as..

http://thehill.com/homenews/administration/179811-white-house-moves-to-save-postal-service-from-default

http://www.businessinsider.com/things-you-should-know-about-the-us-postal-service-before-it-goes-bankrupt-2011-5

http://www.newsmax.com/Newsfront/Postal-Service-Raise-Debt/2011/08/05/id/406288

It just continues to roll up debt.

A private company would be long gone.

>>But the postal service is bleeding money - our money.
>>
>
>
>Are you sure about that?
>
>"The Postal Service supports itself on sales of postage and mail services, and gets no taxpayer funding"
>
>http://money.cnn.com/2011/08/12/news/economy/post_office_layoffs/
>
>or
>
>"The Postal Service, founded in 1775 with Benjamin Franklin as the original Postmaster General, receives all of its money from revenue, just like a private business."
>
>again from same source, different article:
>
>http://money.cnn.com/2009/05/08/news/economy/postal_service/index.htm
>
>or different source
>
>"In 1982, U.S. postage stamps became "postal products," rather than a form of taxation. Since then, The bulk of the cost of operating the postal system has been paid for by customers through the sale of "postal products" and services rather than taxes."
>
>http://usgovinfo.about.com/od/consumerawareness/a/uspsabout.htm
>
>from the same link above
>
>"The USPS does get some taxpayer support. Around $96 million is budgeted annually by Congress for the "Postal Service Fund." These funds are used to compensate USPS for postage-free mailing for all legally blind persons and for mail-in election ballots sent from US citizens living overseas. A portion of the funds also pays USPS for providing address information to state and local child support enforcement agencies.
>
>Under federal law, only the Postal Service can handle or charge postage for handling letters. Despite this virtual monopoly worth some $45 billion a year, the law does not require that the Postal Service make a profit -- only break even. Still, the US Postal Service has averaged a profit of over $1 billion per year in each of the last five years. Yet, Postal Service officials argue that they must continue to raise postage at regular intervals in order make up for the increased use of email."
>
>From a yet different source
>
>"Currently, the U.S. Postal Service receives 99 percent of its operational budget from the sale of postal products (stamps) and postal services. The remaining 1 percent comes from the U.S. Government. This 1 percent is compensation for “free franked mail” for members of Congress; “free mail” for members of the military; and reduced rates for non-profit mailers — i.e. churches, charities, etc."
>
>http://www.jdnews.com/articles/bodycopyrag-67049-class-responsible.html