Portacloy (Irish: Port an Chlóidh) is a Gaeltacht village and townland in northwest County Mayo, Ireland. In the barony of Erris and parish of Kilcommon, it is on the north of the Dún Chaocháin peninsula. The townland is on a horseshoe-shaped bay with two piers and several cliff walks. Portacloy townland has an area of approximately 995.3 acres (4.0277 km) and, as of 2011, had a population of 28.

An area known as "Clayport" at the eastern side of Porturlin began supplying clay for earthenware in 1812. The 1838 Ordnance Survey map showed an old mill, coastguard station, and boathouse at the site of the village.

A road from Glenamoy to Portacloy was completed in 1846. Relief Works during 1846-1847 included building a new road from Portacloy to Cornboy Chapel.

The Society of Friends, noted the challenges faced in fishing due to severe weather and the lack of secure landing ports in the Portacloy area. Efforts in the 1880s aimed at securing a pier for Portacloy, met with resistance, citing limited resources for construction and an exposed setting.

The Congested Districts Board constructed a boat slip, breakwater, landing place, and approach road at Portacloy. Later developments included a bridge and a pier built in the 1960s. Telephone lines extended here during World War II for defence but ceased post-war.

Benwee Head sits just beyond the entrance of the harbour. Charles Browne in an ethnographic study in 1893 described the terrain as rugged, primarily composed of marshland and mountain, with the weather remaining temperate with rare and short-lived frost or snow, yet with heavy rains persisting almost constantly for most of the year, accompanied by frequent and intense storms. Despite the flourishing vegetation, Browne found that trees were sparse due to relentless storms, only growing in sheltered areas.

Portacloy Bay was a Green Coast Award Beach for 2017 and is the starting and finishing point for an 18 km long loop walk.

• List of towns and villages in the Republic of Ireland