Carrickfergus is a large town in County Antrim, Ireland. It had a population of 27,201 people in the 2001 Census. The town is the administrative centre for Carrickfergus Borough Council.

Carrickfergus is a former United Kingdom Parliament constituency, in Ireland, returning one MP.

Carrickfergus was a constituency represented in the Irish House of Commons from 1326 to 1800.