Prefix Information

The prefix 503 is part of area code 312 serving Chicago, Illinois.

This exchange contains 10,000 possible phone numbers (312-503-0000 through 312-503-9999).

Browse Numbers in This Prefix

312-503-0000-0999 312-503-1000-1999 312-503-2000-2999 312-503-3000-3999 312-503-4000-4999 312-503-5000-5999 312-503-6000-6999 312-503-7000-7999 312-503-8000-8999 312-503-9000-9999

Sample Numbers

(312) 503-0000 (312) 503-1234 (312) 503-2000 (312) 503-3333 (312) 503-4444 (312) 503-5555 (312) 503-6000 (312) 503-7777 (312) 503-8888 (312) 503-9999