Postal Preservation Act This bill provides additional funding to the U.S. Postal Service (USPS) in response to the COVID-19 (i.e., coronavirus disease 2019) pandemic. Specifically, the bill appropriates $25 billion to the USPS for its Postal Service Fund for revenue forgone due to COVID-19 and $15 billion for its Office of Inspector General. The bill requires the USPS, during the pandemic, to prioritize the purchase of, and make available to all USPS employees and facilities, personal protective equipment and to conduct additional cleaning and sanitizing of USPS facilities and delivery vehicles. The Office of Inspector General shall (1) conduct oversight, audits, and investigations of projects and activities carried out with appropriated funds; and (2) initiate an audit of the use of such appropriations and report to Congress.