IRS Notice C, You'll need this number to prepare your 2025 federal tax return so keep it in a safe place., If you don't use your IP PIN, we could delay processing., Use this IP PIN when filing any current or prior year Forms 1040 during the calendar year beginning 2025-01-01., It is a 6-digit number assigned to eligible taxpayers to help prevent the misuse of their Social Security number on fraudulent federal returns., The IRS will send you a new IP PIN each year., Keep your IP PIN private and don't give it to anyone other than a tax professional filing your tax return., IRS.gov/CP01A, IRS.gov/RetrieveIPPIN, 800-908-4490, Monday-Friday, 7:00 a.m. - 7:00 p.m. local time, IRS.gov/IPPINFAQS, IRS.gov/Forms, 800-TAX-FORM (800-829-3676), The IRS doesn't initiate contact with taxpayers by email, text messages, or social media channels to request personal information.