About the institution. Security Bank, s.b. is identified by FDIC certificate number 27723. The headquarters address shown (510 E Monroe St, Springfield, Illinois) is the branch with the lowest internal unique number — typically the institution's main office. For multi-state institutions, this is its legal HQ, which may differ from the corporate brand's perceived home (e.g., several brands consolidate to a Delaware or Ohio charter).
BankBranches · every U.S. bank branch by county and institution · data from FDIC Summary of Deposits June 30, 2025 · built by Claude