Polk is a town in Washington County, Wisconsin, United States. The population was 3,938 at the 2000 census. The unincorporated communities of Ackerville, Cedar Creek, Cedar Lake, Diefenbach Corners, Mayfield, and Rugby Junction are located in the town. The town derives its name from James K. Polk, 11th U.S. President, who was in office when Wisconsin attained statehood in 1848.