838) is legislation enacted by the United States Congress and signed into law on December 20, 1944, which established a 50–50 formula for subsidizing the construction of national highways and secondary (or "feeder") roads.

President Franklin D. Roosevelt saw highways as both essential to national defense and the economy, as well as a means of putting unemployed people to work.

Although the financial exigencies and materials shortages of World War II would not permit construction of an interstate highway system, post-war planning was at the top of the legislative agenda.

On December 12, the House and Senate both passed the report of the conference committee, sending the legislation to President Roosevelt.

Among the act's provisions were:[8] Although funds were authorized for the construction of interstate and secondary/feeder roads, appropriations (money actually put into accounts by the United States Treasury) for interstate highways were not made until passage of the Federal Aid Highway Act of 1956.