33440 -- U.S. ZIP code Municipality (1990): CLEWISTON, Florida All ZIPs for this municipality (1990): 33440 Population (2000): 18227 Housing Units (2000): 6898 Land area (2000): 682.871233 sq. miles (1768.628298 sq. km) Water area (2000): 8.719194 sq. miles (22.582609 sq. km) Total area (2000): 691.590427 sq. miles (1791.210907 sq. km) Located within: Florida (FL) Location: 26.714088 N, 80.997300 W