Brewster is a city in Okanogan County, Washington, United States. The population was 2,370 at the 2010 census.
In 1811, John Jacob Astor's Pacific Fur Company established Fort Okanogan just north of the present site of Brewster, which was the first American post in Washington. In 1859, the area experienced a gold rush, and by 1880, steamboats had become a common sight on the Columbia River as far north as Brewster. Most of the settlers in the area were cattle and sheep ranchers. Brewster was officially incorporated on April 29, 1910. The construction of the railroad through Brewster in 1914 created more opportunities for the region, including mining and logging.
The economy of Brewster currently depends on the fruit industry. Four warehouses in the town pack several million boxes of fruit annually. These warehouses are supported by thousands of acres of orchards in the surrounding countryside.