Cathcart is a census-designated place (CDP) in Snohomish County, Washington, United States.

According to the United States Census Bureau, the CDP has a total area of 3.9 square miles (10.0 km2), all of it land.

As of the census[2] of 2000, there were 3,015 people, 1,016 households, and 815 families residing in the CDP.

The racial makeup of the CDP was 94.16% White, 0.46% African American, 0.46% Native American, 0.80% Asian, 0.23% Pacific Islander, 1.39% from other races, and 2.49% from two or more races.

14.5% of all households were made up of individuals, and 3.0% had someone living alone who was 65 years of age or older.