Trust Fund

Trust funds are funds that are designated by law as trust funds. They are usually financed by earmarked collections. A trust fund must use its income for the purposes designated by law, but it is not required to spend them all in the same period they are collected. The five transportation-related federal trust funds are highways, which includes highway and transit accounts; airports and airways; aquatic resource, which is of interest because of the boat safety account; harbor maintenance, and inland waterways. There is also a pipeline safety fund, however, it is not a trust fund. (BTS3)