What is X9?

The Accredited Standards Committee X9 is an ANSI accredited standards developing organization. They’re responsible for creating and maintaining many standards widely accepted by the U.S. financial services industry. They primarily focus on paper and electronic checks, PIN security, and data encryption.

There are many X9 standards out there, several with multiple releases. Our ImageCashLetter project supports the DSTU X9.37-2003 standard for Electronic Exchange of Check and Image Data and its updated versions, which include X9.100-187-2008, X9.100-187-2013, and X9.100-187-2016. Note the standard number was changed from X9.37 to X9.100-187.

A few other X9 standards are closely related to X9.37/X9.100-187, such as TIFF Image Format for Image Exchange (X9.100-181) and Non-Domestic Specifications for Electronic Exchange of Check and Image Data (X9.100-180). If you’re interested in support for additional standards like these, please reach out to us on Slack or open up a GitHub issue.

X9.37 Version Timeline

X9.37-2003 originally released as a draft standard and became widely adopted before being finalized. It was the first major standard to support image cash letters and electronic check exchange. X9.100-187-2008 was published several years later, incorporating fixes and clarifications mentioned in various industry companion documents for X9.37-2003. A backward-compatible maintenance update was released in 2013 and another in 2016 with the sole change of removing return reason codes. There is also a Universal Companion Document for X9.100-187-2016 called TR 47-2016, which helps clarify how financial institutions should use the standard.

It should be mentioned X9.100-180-2006 was meant to be a more flexible replacement for X9.37-2003. While it was fully adopted by Canada, it was ultimately abandoned by the U.S. and is only used in the states for specialized purposes today.