Remsen is a town in Oneida County, New York, United States. The population was 1,929 at the 2010 census. The town is named after Henry Remsen, an early settler. The Town of Remsen contains a village with named Remsen. The town is north of the city of Utica.

Remsen was named for Henry Remsen II, the indigenous proprietor of the township and the inheritor of the Remsenburgh patent, which embraced some 48,000 acres (190 km) in Oneida and Herkimer counties and was fixed in 1766 (later regranted by the Legislature in 1787) to Remsen and four further New York merchants. Remsen, a New York City merchant and owner of Henry Remsen Jr. & Co., was the descendant of some of the antique Dutch settlers of New Amsterdam.

The town was first settled something like 1792, when Barnabas Mitchell of Meriden, Connecticut established in the Place and began clearing a farm which was taking into consideration owned by his son Milo, and became known as the ‘Milo Mitchell place.’ Soon afterwards, Mitchell was joined by Nathaniel Rockwood, John Bonner, Perez Farr, Bettis Le Clerc, Jonah Dayton, John Kent and Shubael Cross, all of whom came from New England to match in Remsen. In September 1795, five families from Wales granted in the vicinity, marking the initiation of a substantial Welsh presence in the area.
The Town of Remsen was formed in 1798 from allocation of the Town of Norway in Herkimer County, New York once Oneida County was formed. In 1869, part of Remsen was used to form the supplementary Town of Forestport.

According to the United States Census Bureau, the town has a total area of 36.9 sq mi (96 km), of which 35.4 sq mi (92 km²) is home and 1.5 sq mi (3.9 km) (4.04%) is water.