The IRS has announced that the Filing Information Returns Electronically (FIRE) system will be retired after the 2026 tax year. Beginning with the 2027 tax year, information returns that historically have been filed through FIRE must instead be submitted using the IRS’ Information Returns Intake System (IRIS). This change affects electronic filings of Forms 1099 (including 1099-R) and 1042-S, among others.

Once FIRE is retired, all affected information returns must be filed through IRIS. Electronic filing through IRIS requires an IRIS Transmitter Control Code (TCC), which is a unique five character alphanumeric identifier. In anticipation of the transition, the IRS has been encouraging filers to apply for an IRIS TCC well in advance of the FIRE retirement date and has not announced any extension or delay of that date. The IRS provides a tutorial on applying for a TCC in Publication 5903 (Rev. 12-2024).

IRIS is a modernized platform that imposes enhanced validation rules, improved security requirements, and different data submission methods, which may require filers to modify existing systems and internal procedures. The FIRE system was designed using legacy file structures and transmission methods that are fundamentally different from those required under IRIS.

IRIS Filing Methods and Technical Considerations

IRIS supports two filing methods, and the technical requirements differ depending on the method used.

The IRIS Taxpayer Portal permits filers to upload information returns in a CSV file format; XML files are not required for portal based submissions. This method is generally designed for filers with moderate filing volumes and more manual or semi manual upload processes.

Alternatively, the application to application (A2A) interface allows for automated system to system transmission of information returns. For A2A submissions, the IRS requires that all returns be transmitted in XML format. CSV files are not accepted through this method. The A2A interface is typically more appropriate for filers with high volume reporting obligations; implementing A2A connectivity is an IT intensive project appropriate for large vendors.

In addition to file format differences, IRIS imposes submission constraints that vary by filing method. Filers using the IRIS Taxpayer Portal are currently limited to 250 information returns per CSV file, as reflected in the IRS’s February update to Publication 5717. This limit applies on a per file basis; however, filers may submit multiple CSV files for the same tax year and form type. For example, a filer with 800 information returns to report may submit four separate CSV uploads of up to 250 records each. By contrast, A2A submissions are not subject to a per record filing limit. Instead, A2A transmissions have a current maximum of 100 MB per transmission.

Compliance Considerations and Next Steps

The transition from FIRE to IRIS does not change the information reporting requirements applicable to Forms 1099 or 1042-S or the due dates for furnishing statements or filing returns.

As IRIS becomes the new (and only) system for electronic filing of federal information returns, filers may experience higher rejection rates due to IRIS validation guidelines. Minor errors that might have been overlooked before may cause a rejection now.

Affected filers should begin preparing for IRIS now by:

• obtaining an IRIS TCC;
• evaluating whether portal based filing or A2A transmission is appropriate; and 
• confirming whether internal systems or third party vendors support the appropriate IRIS filing method.

Because formal IRS testing through the IRIS Assurance Testing System is available for A2A filers, entities planning to use the A2A interface should conduct test submissions using a test TCC well in advance of applicable filing deadlines. Filers using the IRIS Taxpayer Portal should allow sufficient time before filing deadlines to validate CSV file formatting and address any errors identified through the portal’s pre submission error checks.

Additional information can be found on the IRS website regarding e-file information returns with IRIS. Ice Miller will continue to monitor developments related to the transition to IRIS and provide updates if additional guidance becomes available. Please do not hesitate to contact Audra J. Ferguson, Robert L. Gauss, Nicole Giambarrese, Lisa Erb Harrison, Lindsay Knowles, Rachel Mattingly Phillips, Stanley D. Prybe, Shalina Ann Schaefer, Chris Sears, or the Ice Miller Employee Benefits lawyer with whom you regularly work.

This publication is intended for general information purposes only and does not and is not intended to constitute legal advice. The reader should consult with legal counsel to determine how laws or decisions discussed herein apply to the reader's specific circumstances.