Fabius is a town in Onondaga County, New York, United States.

The region was part of the Central New York Military Tract used to pay soldiers of the American Revolution.

The town was formed in 1798 from Pompey and was one of the original townships in the Military Tract established in 1790.

[3] Fabius lost territory to the new towns of Tully (1806) and Truxton (1808 on the formation of Cortland County).

The town of Fabius and some of the town's 1950s landmarks—the Fabius Central School and the famous Shea's General Store—are featured in the novel, The Pompey Hollow Book Club by Jerome Mark Antil.