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Possible online services disruption due to Internet related outage

A worldwide technology outage is causing disruption to some State of Illinois online systems. We are aware of this issue and are diligently working on restoration.

Substitute Forms Developers

Creating your own version of Illinois Department of Revenue tax forms?

NOTE: If your substitute forms print from electronic filing software you develop, you must separately enroll and test your software. See Electronic Transmitters/Software Developers.

NOTE: IL-1040 for Software Developers

Test cases, schemas, and business rules are located on the FTA's State Exchange System (SES). To request access to the SES, email your user's name and email address to Rev.TaxLOI@illinois.gov. You will need to complete the Tax Software Provider Illinois Department of Revenue Letter of Intent, submit it to Rev.TaxLOI@illinois.gov, and obtain approval to access the test cases, schemas, business rules, and developer guide.