It is located in the south-central part of the state, running from southwest to northeast, roughly parallel to Interstate 95 for its entire length.

It runs northward along the eastern side of Messalonskee Lake into the town of Oakland, where it rejoins SR 11 and cuts through downtown.

The two routes overlap northward for just over two miles into the northwestern corner of the town before SR 23 splits off to the northwest and crosses the river into Canaan.

SR 154 abruptly ends after two miles, though, at the intersection with Water Street.

In 1954, the northern terminus of SR 24 was truncated to its current location in Gardiner.