Sinclair Inlet is an arm of Puget Sound in Kitsap County, Washington, USA. It is the southwestern extension of Port Orchard, and it touches the shores of three of Kitsap County's four incorporated cities: Bremerton, Bainbridge Island, and Port Orchard. It is connected to Dyes Inlet by the Port Washington Narrows and to Puget Sound by Rich Passage. It was named by United States Navy explorer Charles Wilkes for George T.