Post offices in the county of St. Clair, IL

Use this page to find the post offices in your county that open earliest or stay open latest. The open hours listed are for the post office's retail hours, which means the hours in which a postal service employee is available at the counter to help with mailings and other services. Oftentimes lobbies are open extended hours, and you are able to check your PO box, drop off packages, or use the self-service APC machine to buy postage. The list below is first sorted alphabetically by city, then by post office name. Street View photos of post offices are shown when available. Please contact us if you find an error, so that we can correct it.