Belmullet "mouth of the Mullet [Peninsula]") is a coastal Gaeltacht town with a population of 1,019 on the Mullet Peninsula in the barony of Erris, County Mayo, Ireland. It is the commercial and cultural heart of the barony of Erris, which has a population of almost 10,000. According to the 2016 census 50% of people in the town were able to speak Irish while only 4% spoke it on a daily basis outside the education system.

Belmullet has two bays, Blacksod Bay and Broadhaven Bay, linked by Carter's Canal running through the town.