Puerto Williams (Spanish for "Port Williams") is a Chilean port, located on Isla Navarino facing the Beagle Channel. It is the capital of the Chilean Antarctic Province, one of four provinces located in the Magellan and Chilean Antartica Region. It has a population of a over 2,200, including both naval personnel and civilians. Puerto Williams is often referred to as the world's southernmost city which is often disputed by the larger city of Ushuaia, Argentina, located to the northwest.

The settlement was named after John Williams Wilson, who founded Fuerte Bulnes, the first settlement in the Strait of Magellan since 1587. Puerto Luisa was its original name. Since its foundation in 1953 the settlement has served primarily as a naval base. But recently navy personnel living in Puerto Williams have decreased while civil population has increased. In recent years tourism has contributed to an increase in economic activity at Puerto Williams. Universidad de Magallanes has a university centre in Puerto Williams.