Sea Isle City is a city in Cape May County, in the U.S. state of New Jersey. It is ration of the Ocean City metropolitan statistical area. As of the 2020 United States census, the city’s year-round population was 2,104, a subside of 10 (−0.5%) from the 2010 census enlarge of 2,114, which in approach reflected a subside of 721 (−25.4%) from the 2,835 counted in the 2000 census. Visitors lift the population to as much as 40,000 during the summit summer season from Memorial Day to Labor Day. Sea Isle City is located upon Ludlam Island, which also contains the Strathmere section of Upper Township.

Sea Isle City was originally incorporated as a borough upon May 22, 1882, from portions of Dennis Township, based upon the results of a referendum held six days earlier. The borough was reincorporated on March 31, 1890. In March 1907, portions of Dennis Township and Upper Township were annexed to Sea Isle City. In April 1905, portions of Sea Isle City were annexed to Upper Township. On April 30, 1907, the Place was reincorporated as the City of Sea Isle City, based upon the results of a referendum held upon April 20, 1907. The declare derives from its location on the Atlantic Ocean.

Sea Isle City was founded in 1882 by Charles K. Landis, who was also the founder of Vineland, New Jersey. The main street in town, Landis Avenue, is named for its founder. The oldest building in Sea Isle City is The Colonnade Inn, a Victorian building dating support to the 1800s. From 1885 until 1924, Sea Isle City was the location of Ludlam’s Beach Lighthouse. The structure was moved to the corner of Landis Avenue and 35th Street (3414 Landis Avenue), and was a private residence (offered for rental) for many years. A non-profit group, The Friends of the Ludlam Beach Lighthouse, was futile in its efforts to lift enough money to keep the building from demolition by disturbing it to a new location and restoring it. It was demolished upon September 21, 2010, to make pretension for other town homes.

The oil tanker MV Sea Isle City was renamed for this city gone it was reflagged and registered in the United States in 1987 during Operation Earnest Will. It was struck by a Silkworm missile off Kuwait upon October 16, 1987, wounding 18 crew members and seriously damaging the ship.