Finance term
Routing Number
Also known as: ABA routing number, ABA number, routing transit number, RTN
Definition
A routing number (formally ABA routing transit number) is the nine-digit code that identifies a U.S. bank or credit union in electronic transactions. It directs ACH payments, wire transfers, and check processing to the correct financial institution.
Detailed explanation
Routing numbers were established by the American Bankers Association (ABA) in 1910 to sort and route paper checks. Today they serve the same function for all electronic payments. The nine-digit format encodes a Federal Reserve processing center identifier (digits 1–4), an ABA institution identifier (digits 5–8), and a check digit (digit 9) for validation.
Large banks may have multiple routing numbers for different regions or transaction types. Wells Fargo, for example, has separate routing numbers for each state. The number on the bottom left of a check is the routing number; the account number follows it.
For ACH transactions — direct deposit of payroll, bill payments, peer-to-peer transfers — both the routing number and account number (your specific account identifier) are required. The Federal Reserve processes ACH transactions through its FedACH service; The Clearing House (TCH) operates the private-sector RTP (real-time payments) network alongside it. Providing incorrect routing information delays transactions and can result in returned payments.
◈ Worked example
- The ABA routing number for JPMorgan Chase (California) is 322271627 — different from Chase's New York routing number (021000021).
- When setting up direct deposit, your employer's payroll system uses your routing number + account number to credit your paycheck via ACH.
Common questions
The most-asked questions about Routing Number — answered straightforwardly.
Where do I find my routing number? +
Bottom left of a personal check, in your bank's mobile app under account details, or on your bank's website. You can also look it up by bank name on the ABA's public routing number database at routingnumbers.aba.com.
Is my routing number the same as my account number? +
No. The routing number identifies the bank; the account number identifies your specific account at that bank. Both are needed for ACH and wire transfers.
Further reading
This glossary entry is educational content. ClearValue Lending is a business & personal financing platform — not a lender, broker, or financial advisor. Specific product terms vary by lender; verify with the lender or issuer before applying. See privacy policy.