There's none. All of the branches listed at Regions website are closed on Saturdays. However, you might get some help on their drive-thru service available at the following branches during Saturdays from 9:00-12:00.
Regions University Oaks Branch - 5202 Cottage Hill Road, Mobile, AL 36609; T: 8007344667
Regions Belair Branch - 3001 Airport Boulevard, Mobile, AL 36606; T: 8007344667
Of interest, Key International Development has received funding from Regions Bank for a 230-unit project in Sunny Isles Beach, Florida. Find out how much Regions Bank gave to this project at South Florida Business Journal.