61811 -- U.S. ZIP code Municipality (1990): ALVIN, Illinois All ZIPs for this municipality (1990): 61811 Population (2000): 800 Housing Units (2000): 302 Land area (2000): 23.632443 sq. miles (61.207743 sq. km) Water area (2000): 0.000000 sq. miles (0.000000 sq. km) Total area (2000): 23.632443 sq. miles (61.207743 sq. km) Located within: Illinois (IL) Location: 40.293159 N, 87.614017 W