Routing Number / Sort Code
A numeric code that identifies a specific bank or branch within a national payment network, used to direct domestic transfers to the correct institution.
Also known as: ABA routing number, sort code, bank routing number, transit number
Last reviewed: 10 June 2026
In the United States, a routing number (also called an ABA routing number) is a nine-digit code that identifies the financial institution for domestic ACH and wire transfers. In the United Kingdom, a six-digit sort code performs the same function, identifying the bank and specific branch. Together with the account number, these codes form the minimum information needed to initiate a domestic transfer.
Because routing/sort codes and account numbers are all that is needed to pull money out of an account via ACH or direct debit, this information should be treated as sensitive. Fraudsters who obtain your routing number and account number can set up unauthorised ACH debits.
Be cautious about where you share these details. Legitimate employers need them for payroll; legitimate utility companies need them for direct debit — but unsolicited requests for your routing and account number should always be questioned.