Modulus checking

What is modulus checking?

Modulus checking is a fast and efficient way to validate customer payment details, before submitting a Bacs Direct Credit or Direct Debit instruction.


Why is it important?

By validating the details first, you reduce the likelihood of getting failed payments, lowering the risk of human error and fraud. It can also minimise time spent on investigating failed payments, and improve your cashflow.

How does it work?

Modulus checking uses a mathematical algorithm to compare customer account numbers and sort codes, and check if the two can be paired together legitimately. Vocalink’s service offers the most comprehensive coverage of UK financial institutions available, and is regularly updated to include the latest changes.

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Downloads

Validating Account Numbers

Valid from 5 October 2021

Modulus weight table data

Valid from 5 October 2021

Sorting Code Substitution Data

Valid from 13 June 2005

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