United States Post Office 11135 San Pablo Ave, El Cerrito, CA94530 This branch of the USPS is one of two locations in El Cerrito. This location is open most often. The medium-sized lobby…More usually has two-to- three attendants serving customers. There are many P.O. boxes available to rent here, as well as counters set up to add finishing touches to your mail before you send it out. Supplies are also available to purchase such as tape, envelopes and bubble packages for fragile items.