Foul Rift is an unincorporated community and one-time ghost town located within White Township, in Warren County, in the U.S. state of New Jersey.

[1][2] Foul Rift had been a cottage community located on the east bank of the Delaware River, 2 mi (3.2 km) south of Belvidere.

[3] A tract of 1,735 acres (702 ha) was surveyed to William Penn, "extending from the foot of Foul Rift to Hutchison's".

Early settlers to Foul Rift purchased land from Penn's heirs in 1740.

The Rifton Mills were built there in 1814 in order to harness the fast flowing water at Foul Rift.