What is IRS e-file reject code IND-181?
IRS will reject an e-file and report rejection code IND-181 if at some past point of time you joined IRS "Identity Protection PIN" program (maybe due to identity theft). You’d need your current tax year 6 digit PIN issued by IRS to e-file your return.
You’d retrieve that PIN from the letter IRS mailed you in January of the current tax year or online at https://www.irs.gov/identity-theft-fraud-scams/get-an-identity-protection-pin
In an effort to combat federal income tax related identity theft, the IRS revised its 1040 series electronic tax forms to allow for the entry of a 6-digit "Identity Protection PIN."
Starting January 2014, IRS sends LTR4869CS letters to taxpayers who have contacted IRS and have been validated as being victims of identity theft that has affected the filing of their federal income tax return. The letter contains a single use 6 digit Identity Protection PIN. The Identity Protection PIN may begin with a zero. The PIN annually issued in January of each tax year will be applicable only for that tax year. Taxpayers receive a letter and code each year in January for a period of 3 years following the last validated incident.