Altos Bank Routing Number

What is an ABA routing number?

An ABA routing number, also called a routing transit number (RTN), is a 9-digit code that identifies a U.S. financial institution in the payment system. It tells ACH transfers, Fedwire payments, and paper checks which bank to route money to. The format was created by the American Bankers Association in 1910 and is still the backbone of U.S. domestic payments.

What is the difference between a routing number and an account number?

Your routing number identifies the bank; your account number identifies your specific account at that bank. On a paper check, the routing number is the 9-digit number in the bottom-left, and the account number is to its right.

What is the Altos Bank routing number?

The Altos Bank routing number is 121145491. It is the primary ABA routing transit number registered to Altos Bank, headquartered in Los Altos, CA. A bank can hold more than one routing number, so this is the one on record for the institution, not necessarily the one printed on every check. The number comes from the FFIEC National Information Center institution record, last refreshed here on October 8, 2026.

What is the Altos Bank wire routing number?

This page lists 121145491, the primary routing number registered to Altos Bank. The record does not say whether the bank uses the same number for wire transfers, and many banks use a separate routing number for domestic wires. Confirm the wire routing number with Altos Bank before sending a wire.

Is ABA number 121145491 the routing number for Altos Bank?

Yes. ABA number 121145491 is the primary routing number registered to Altos Bank. Check it against the routing number on a check or in your online banking before sending an ACH payment, because a bank can use different numbers by region or product.

Which bank uses routing number 121145491?

Routing number 121145491 belongs to Altos Bank, headquartered in Los Altos, CA. It is the bank's primary ABA routing number (FDIC certificate 59339).

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