Portrush ( ) is a seaside resort town in County Antrim, Northern Ireland, on the County Londonderry border. The main part of the old town, including the railway station, most hotels, restaurants and bars, is built on a mile-long peninsula, Ramore Head, pointing north-northwest. It had a population of 6,372 people in the 2001 Census. In the off-season, Portrush is a dormitory town for the nearby campus of the University of Ulster at Coleraine. It neighbours the resort of Portstewart.

It is the base for the Katie Hannan, a Severn class lifeboat and Ken and Mary, a D-class inshore lifeboat of the RNLI. Lifeboats have operated out of Portrush Harbour since 1860.

Portrush is in the East Londonderry constituency for the UK Parliament and Northern Ireland Assembly.