Houat (Breton: Enez Houad; French: Île d'Houat, French pronunciation: [il dwat]) is a French island off the south coast of Brittany in the department of Morbihan. It is located, along with two other major islands, in the entrance to the Baie de Quiberon. Its "twin sister" island is Hoëdic.

Administratively, Île-d'Houat is a commune of the Morbihan department.

5 km (3.1 mi) long, 1.5 km (0.93 mi) at the widest. The island is mostly granite cliffs except for a long beach lined with dunes on the eastern coast.

Inhabitants of Île-d'Houat are called Houatais.

Houat is the setting for Iain Pears' 2005 novel The Portrait.

• Communes of the Morbihan department

• Base Mérimée: Search for heritage in the commune, Ministère français de la Culture. (in French)