AT&T in Belleville, IL
These numbers are located in the city of Belleville part of St. Clair county. There are a few other subcodes that cover this area as well so take care not to confuse them.
St. Clair county is situated in Illinois and operates CT (UTC -06:00) time. This number group covers the 62220, 62226, 62221, & 62222 zip codes.