Langley is a city in Island County, Washington, United States. It sits at the south end of Whidbey Island, overlooking the Saratoga Passage. The city's population was 1,035 at the 2010 census, while the ZIP Code Tabulation Area for Langley's post office had a population of 4,878. By the 2020 census, the population increased to 1,147 people. Langley proper only covers 0.8 square miles, but its ZCTA extends for 26.20 square miles.