An IP PIN is a six-digit number that help prevent someone from filing a tax return using your Social Security Number (SSN) or Individual Taxpayer Identification Number (ITIN). The IP PIN is known only to you and the IRS and helps verify your identity when you file your tax return.
The IP PIN is valid for one year, so each January, you’ll need a newly-generated IP PIN. Most taxpayers can obtain an IP PIN by applying at IRS.gov/ getanippin. You must pass the identity proofing requirements. But if you can’t successfully validate your identity through online means, you may apply with Form 15227.
After you’re assigned an IP PIN, it must be entered accurately on electronic and paper tax returns to avoid rejection and delays.