O'Fallon, Illinois

Nearest ZIP codes to O'Fallon

These are the ZIP codes nearest to O'Fallon, each listed with the post office it is named after.

Area codes for O'Fallon

• Area code 618

  In service since 1947. Shares its area with 730. Local calls are dialed with ten digits; dialing 1 plus ten digits also works.

• Area code 730

  In service since July 7, 2023. Shares its area with 618. Local calls are dialed with ten digits; dialing 1 plus ten digits also works.

Area codes here are matched from telephone rate centers, so a place near a boundary can have local numbers from either side of it.

Time zone

O'Fallon is in the Central Time zone.

Towns near O'Fallon

• O Fallon3.6 km (2.2 mi)
• Shiloh5.6 km (3.5 mi)
• Fairview Heights8 km (5.0 mi)
• Scott Air Force Base8 km (5.0 mi)
• Swansea8.2 km (5.1 mi)
• Scott AFB8.4 km (5.2 mi)
• Caseyville9.3 km (5.8 mi)
• Lebanon10.1 km (6.3 mi)