Prefix Information

The prefix 203 is part of area code 312 serving Chicago, Illinois.

This exchange contains 10,000 possible phone numbers (312-203-0000 through 312-203-9999).

Browse Numbers in This Prefix

312-203-0000-0999 312-203-1000-1999 312-203-2000-2999 312-203-3000-3999 312-203-4000-4999 312-203-5000-5999 312-203-6000-6999 312-203-7000-7999 312-203-8000-8999 312-203-9000-9999

Sample Numbers

(312) 203-0000 (312) 203-1234 (312) 203-2000 (312) 203-3333 (312) 203-4444 (312) 203-5555 (312) 203-6000 (312) 203-7777 (312) 203-8888 (312) 203-9999