What this notice is about We revoked your qualified subchapter S trust (QSST) election. What you need to do Timely file Form 1041, U.S. Income Tax Return for Estates and Trusts (PDF). You may want to Keep this notice for your permanent records. Reference Tools Publication 1, Your Rights as a Taxpayer (PDF) Form 15100, Adoption Taxpayer Identification Number (ATIN) Extension Request (PDF) Full list of tax forms and instructions Need Help? You can authorize someone to contact the IRS on your behalf. See if you qualify for help from a Low Income Taxpayer Clinic. If you can’t find what you need online, call the IRS number at the top of your notice or letter.