What Is the Highway Trust Fund?
The Highway Trust Fund (HTF) was created by the Highway Revenue Act of 1956 (Pub. L. 84-627), primarily to ensure a dependable source of financing for the National System of Interstate and Defense Highways and also as the source of funding for the remainder of the Federal-aid Highway Program. Prior to the creation of the HTF, federal financial assistance to support highway programs came from the General Fund of the U.S. Treasury. While federal motor fuel and motor vehicle taxes did exist before the creation of the HTF, the receipts were directed to the General Fund, and there was no relationship between the receipts from these taxes and federal funding for highways. The Highway Revenue Act authorized that revenues from certain highway-user taxes could be credited to the HTF to finance a greatly expanded highway program enacted in the Federal-Aid Highway Act of 1956.
In the original Highway Revenue Act of 1956, the crediting of user taxes to the HTF was set to expire at the end of fiscal year 1972, but since then, legislation has been passed to extend the imposition of the taxes and their transfer to the HTF through September 30, 2005.
Like other federal trust funds, the HTF is a financing mechanism established by law to account for tax receipts that are collected by the federal government and are dedicated or "earmarked" for expenditure on special purposes. Originally, the HTF focused solely on highways, but later Congress determined that a portion of the revenues from highway-user taxes dedicated to the HTF should be used to fund transit needs, resulting in a 5 cent increase in the gas tax (to 9 cents), of which 1 cent would go towards transit, to help fund the new account. As a result, the Mass Transit Account was created within the HTF effective April 1, 1983. Although never formally described and named, the portion of the Highway Trust Fund outside the Mass Transit Account has come to be called the Highway Account and receives all HTF receipts not specifically designated for the Mass Transit Account.
How is the HTF funded?
Tax revenues directed to the HTF are derived from excise taxes on highway motor fuel and truck-related taxes on truck tires, sales of trucks and trailers, and heavy vehicle use. The Mass Transit Account receives a portion of the motor fuel taxes, usually 2.86 cents per gallon, as does the Leaking Underground Storage Tank Trust Fund, usually 0.1 cent per gallon. The General Fund receives 2.5 cents per gallon of the tax on gasohol and some other alcohol fuels plus an additional 0.6 cent per gallon for fuels that are at least 10 percent ethanol. The Highway Account receives the remaining portion of the fuel tax proceeds.
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