Postpayment Audits

Since the enactment of the Transportation Act of 1940, GSA’s Transportation Audits Division has been required to perform a postpayment audit on all federal agency paid transportation bills. A postpayment audit is a thorough review and validation of transportation related bills. During an audit, bills are examined for validity, propriety, and conformity of the charges using tariffs, quotations, agreements, or tenders as appropriate.

Federal agencies are required to submit all paid transportation bills monthly to GSA. Paid transportation bills can be submitted by email to QMCATariffs, subject: “Post Pay Docs”.

Paper copies or transportation bills saved on compact disks can be submitted to:

General Services Administration
FAS Transportation Audits Division (QMCAB)
Room 1033
1800 F Street, NW
Washington DC 20405

Also, include with your submitted paid transportation bills a completed Agency Invoice Log and Standard Form 1186, Transmittal for Transportation Schedules. All documents should be submitted by the 15th of each month. Reference the Transportation Handbook and Regulations web page for the Agency Invoice Log and Standard Form 1186. If further assistance is needed, please send an email to the Disputes Resolution Branch at

GSA’s postpayment audit includes, but is not limited to:

  • Audit selected TSP bills after payment;
  • Audit selected TSP bills before payment, as needed to protect the Government’s interest (i.e. bankruptcy, fraud;
  • Examine, settle, and adjust accounts involving payment for transportation and related services for the account of agencies;
  • Adjudicate and settle transportation claims by and against agencies;
  • Offset an overcharge by any TSP from an amount subsequently found to be due that TSP;
  • Issue a Notice of Overcharge stating that a TSP owes a debt to the agency; and
  • Issue a GSA Notice of Indebtedness when a TSP owes an ordinary debt to an agency.

The Transportation Audits Division, in conjunction with three audit contracting companies, review an average of over 12 million transportation invoices per year, recovering millions of dollars in the process. Funds recovered because of post payment audits are returned to the Treasury Department.

Last Reviewed: 2019-10-31