63751 -- U.S. ZIP code Municipality (1990): GLENALLEN, Missouri All ZIPs for this municipality (1990): 63751 Population (2000): 1029 Housing Units (2000): 445 Land area (2000): 59.609577 sq. miles (154.388090 sq. km) Water area (2000): 0.072024 sq. miles (0.186541 sq. km) Total area (2000): 59.681601 sq. miles (154.574631 sq. km) Located within: Missouri (MO) Location: 37.332487 N, 90.086750 W