312 serves the Chicago Loop of the city of Chicago, Illinois. It encompasses only a few square miles, roughly bounded by North Avenue to the north, Ashland Avenue to the west, Lake Michigan on the east, and 31st Street on the south.
- 312-295
- Cell Number
- La Grange Park, IL
- 312-318
- Cell Number
- La Grange Park, IL
- 312-366
- Cell Number
- La Grange Park, IL
- 312-367
- Cell Number
- La Grange Park, IL
- 312-403
- Cell Number
- La Grange Park, IL
- 312-501
- Cell Number
- La Grange Park, IL
- 312-717
- Cell Number
- La Grange Park, IL
- 312-968
- Cell Number
- La Grange Park, IL
- 312-969
- Cell Number
- La Grange Park, IL
