Raritan Bay is a triangular bay in the western portion of Lower New York Bay, between the U.S. states of New York and New Jersey. It located at the confluence of the Arthur Kill and the Raritan River, which flows into the bay from the west. The bay is bounded on the north by Staten Island in New York City and on the south by Monmouth County, New Jersey.

The bay and river are named after the Raritans, a tribe of the Lenape, who lived in the immediate area around the bay during the 17th century at the time of the arrival of the Dutch colonists.

Throughout the history, the bay has been a prime fishing ground, especially for commercial oyster fishing, until the 20th century. The bay is crossed by a dredged channel allowing commercial ships to enter the Arthur Kill.

See also

• Geography of New York Harbor
• Sandy Hook Bay