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 2018 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, and business rules.