San Mateo Credit Union Routing Number: Bay Area CU Guide

What is the San Mateo Credit Union routing number?

San Mateo Credit Union's routing number is 321172594. This routing number applies to all SMCU accounts including checking, savings, and money market accounts across all San Mateo County branch locations.

San Mateo Credit Union has served the San Francisco Peninsula community since 1952. Originally chartered for San Mateo County employees, membership is now open to anyone who lives, works, worships, or attends school in San Mateo County.

Locating your SMCU routing number

You can find routing number 321172594 on the bottom-left of your San Mateo Credit Union checks, through the SMCU mobile app, or by logging into online banking. Branch staff can confirm the number as well.

The 321 prefix identifies SMCU within the Federal Reserve Bank of San Francisco processing district, which handles transactions for Bay Area financial institutions.

Direct deposit and ACH transactions

Use routing number 321172594 and your account number to enroll in direct deposit with your employer. SMCU processes payroll, tax refund, and government benefit deposits through the ACH network efficiently.

ACH bill payments and external transfers can be initiated through SMCU's online banking. Incoming ACH transactions are received without additional fees and typically settle within one to two business days.

Wire transfer information

Domestic wire transfers at SMCU use routing number 321172594. Outgoing wires can be arranged through a branch visit. Incoming domestic wires are posted to your account on the same business day when received before cutoff.

For international wire transfers, contact SMCU member services for correspondent bank details and SWIFT code requirements. Standard fees apply for both incoming and outgoing international wires.

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