Check 21 and IRDs


Frequently Asked Questions


What is Check 21?

The Check Clearing for the 21st Century Act, also known as the Check 21 Act or Check 21 took effect on October 28, 2004 and requires that all banks be able to accept an electronic image of a check rather than the paper check itself.

Banks who wish to send electronic check images scan the checks to create electronic files and then destroy the original paper check.  The electronic image may be re-printed onto a new type of document called an Image Replacement Document (IRD) or Substitute Check.  Since the IRD replaces the original check, it is a legal negotiable document, subject to the same conditions and regulations as an ordinary check.

What are Image Replacement Documents (IRDs) or Substitute Checks?

A legally negotiable document, the electronic image of a check is called the Image Replacement Document of Substitute Check. Relyco provides IRD paper and Substitute Checks specifically designed to ensure Check 21 compliance as well as compliance with the ANSI X9.100-140-2008 technical guidelines for size, layout, paper weight and document security.

Relyco IRD Paper is image friendly and provides optimal scanning consistency. Moreover, Relyco’s IRD paper/Substitute Checks incorporate covert and overt security features to deliver protection from fraud and are manufactured on high-quality safety paper for superior laser compatibility. Relyco’s 1-up 8.5” x 11” IRD paper layout is compatible with the PDF delivery program from the Federal Reserve for return substitute checks.

To Learn More

To learn more about Check 21 and Substitute Checks/IRDs from Relyco, call 1-800-777-7359 or email This email address is being protected from spambots. You need JavaScript enabled to view it.