Essex, MO -- U.S. city in Missouri Population (2000): 524 Housing Units (2000): 238 Land area (2000): 0.275127 sq. miles (0.712576 sq. km) Water area (2000): 0.000000 sq. miles (0.000000 sq. km) Total area (2000): 0.275127 sq. miles (0.712576 sq. km) FIPS code: 22600 Located within: Missouri (MO), FIPS 29 Location: 36.812040 N, 89.862514 W ZIP Codes (1990): 63846 Note: some ZIP codes may be omitted esp. for suburbs. Headwords: Essex, MO Essex