Skip to main content

ABA Routing Transit Number & Account Generator (USA)

Generate valid 9-digit ABA Routing Transit Numbers and US bank account numbers for software testing.

Waiting for generation...

About the ABA Routing Transit Number (USA)

The ABA Routing Transit Number (RTN) is a 9-digit bank code regulated by NACHA and the Federal Reserve to identify financial institutions in ACH and Fedwire transfers.

The first two digits identify the Federal Reserve district (01 to 12) or specialty institutions, followed by 6 institution identifier digits and 1 check digit calculated via 3-7-1 Mod 10 weighting.

Anatomy & Structure of ABA Routing Transit Number

The 9-digit US ABA Routing Transit Number (RTN) is structured into clear functional components:

PositionFieldLengthFederal Reserve Meaning & RulesExample
1 & 2Federal Reserve Routing2 digitsIdentifies the Federal Reserve district (01-12) or institution type (21-32 = Thrift, 61-72 = Wire/ACH).02
3 & 4Processing Center2 digitsDesignates the Federal Reserve check processing center.60
5 to 8Institution Identifier4 digitsUnique institution ID within the Federal Reserve district.0582
9Check Digit1 digitChecksum digit calculated using the weighted Modulo 10 algorithm with weights [3, 7, 1].1

ABA Routing Check Digit Algorithm (Federal Reserve Mod 10)

The routing number utilizes a weighted position checksum to prevent routing errors in ACH and Fedwire:

(3(d1 + d4 + d7) + 7(d2 + d5 + d8) + 1(d3 + d6 + d9)) % 10 == 0
  1. 1. Cyclic Weight Multiplication [3, 7, 1]: multiply digits 1, 4, 7 by 3; digits 2, 5, 8 by 7; and digits 3, 6, 9 by 1.
  2. 2. Total Weighted Sum: add all 9 individual products together.
  3. 3. Modulo 10 Check: the total sum must be evenly divisible by 10 (Total Sum % 10 === 0).
  4. 4. Automated Rejection: any routing number failing this check is immediately rejected by ACH and wire systems.

Frequently Asked Questions (FAQ)