What is a routing number?

A routing number — formally called an ABA routing transit number (RTN) — is a 9-digit code assigned by the American Bankers Association to uniquely identify a U.S. bank or credit union in financial transactions. When you set up direct deposit, initiate an ACH transfer, or send a wire, the routing number is what tells the payment network which institution holds (or should receive) the funds. Without the correct routing number, a transfer is misdirected or rejected.

Where to find your routing number

The most reliable places to find your routing number are: (1) the bottom-left corner of a paper check — the 9-digit number printed before your account number; (2) your bank's mobile app or website (usually under account details or settings); (3) your bank's official website or customer service line. Large banks sometimes use different routing numbers for different states or transaction types (ACH vs. wire) — always verify which number applies to your specific transaction type. The Federal Reserve's E-Payments Routing Directory is a free, authoritative lookup tool.

• Routing number: 9 digits, identifies the bank or credit union.
• Account number: your unique account identifier at that institution (separate from the routing number).
• On a check: routing number is the first 9 digits in the bottom-left; your account number follows.
• Wire routing numbers may differ from ACH routing numbers at some large banks — confirm before sending.
• Credit unions use routing numbers the same way banks do.

Routing number vs. account number

The routing number identifies the institution; the account number identifies your specific account at that institution. Both are required for ACH transfers and wire transfers. Think of the routing number as the ZIP code of the financial system — it routes a payment to the right bank — and the account number as the street address that delivers it to your specific account. Neither is a secret in the context of receiving payments (they appear on every check you write), but guard your account number carefully, as it enables ACH debits with authorization.

Checking vs. savings routing numbers

Most banks use the same routing number for both checking and savings accounts. You'll need both the routing number and account number to set up direct deposit — your employer's payroll system uses these two numbers together to identify exactly where to send funds.