Fast Facts

The Airport and Airway and the Highway Trust Funds are the main funding sources for federal aviation and ground transportation programs. User taxes on airline tickets, aviation fuel, tires, and gasoline are their primary source of funding. The IRS is responsible for collecting those taxes and certifying the amounts distributed to the trust funds.

We performed certain procedures that the Department of Transportation Office of Inspector General requested on the tax revenue IRS collected and certified to the trust funds to assist the OIG in auditing DOT's financial statements. We make no overall conclusion on the results of those procedures.

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What GAO Found

Why GAO Did This Study

GAO performed agreed-upon procedures solely to assist the DOT OIG in ascertaining whether the net excise tax revenue distributed to the AATF and the HTF for the fiscal year ended September 30, 2020, is supported by information from the Department of the Treasury, including IRS's excise tax receipt certifications and OTA's estimates. DOT OIG is responsible for the sufficiency of these agreed-upon procedures to meet its objectives, and GAO makes no representation in that respect. The procedures that GAO agreed to perform were related to information representing the basis of amounts distributed from the General Fund to the AATF and the HTF during fiscal year 2020, including (1) IRS's quarterly AATF and HTF excise tax certifications prepared during fiscal year 2020 and (2) OTA's estimates of excise tax amounts to be distributed to the AATF and the HTF for the third and fourth quarters of fiscal year 2020.

For more information, contact Cheryl E. Clark at (202) 512-3406 or

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