Poulsbo is a city on Liberty Bay in Kitsap County, Washington, United States. It is the smallest of the four cities in Kitsap County. The population was 11,970 at the 2020 census and an estimated 10,927 in 2018.

The Suquamish people have inhabited the surrounding area in Lushootseed, for millennia. After the signing of the Treaty of Point Elliott in 1855, many were moved to the Port Madison Indian Reservation. Poulsbo was then founded in the 1880s by Norwegian immigrant Jørgen Eliason, who was joined by other Scandinavians who relocated from the Midwestern states. They were drawn here by the availability of land, by the area's rich resources, and by a landscape similar to their native home. The settlement was connected by boats to other areas of the region, including the Puget Sound mosquito fleet, which was eventually usurped by highways built in the early 20th century.

Until World War II, many Poulsbo residents retained Norwegian as a primary language. However, during World War II, the military constructed about 300 residential units to provide housing for workers at the nearby Puget Sound Naval Shipyard in Bremerton. The population of Poulsbo almost tripled over three years, and the diversification of the population led to the dominance of English as the primary language.

Poulsbo is located in northern Kitsap County at 47°44′21″N 122°38′21″W , at the north end of Liberty Bay, a sheltered arm of Puget Sound. Washington State Route 305 has its northwestern terminus in the northern part of the town at State Route 3 and leads southeast 13 miles to the ferry docks at Bainbridge Island. SR 3 leads north 9 miles to Port Gamble and south 16 miles to the western part of Bremerton.