The IP PIN (Identity Protection PIN) is a 6-digit PIN provided by the IRS to certain victims of ID theft.
A new IP PIN will be generated each year. If the IRS assigned you an IP PIN, you must use it to confirm your identity on any return filed during the current calendar year. This includes current year returns as well as any delinquent tax returns. An IP PIN is used only on Forms 1040, 1040-NR, 1040-PR, 1040-SR and 1040-SS.
The IP PIN is good for the calendar year for which it was issued. It follows the calendar year rather than the tax year for which you are filing. So, if you got an IP PIN in 2024, it is no longer valid and you would need to get a new one for 2025 if you wanted or needed to use one.
If you don't already have an Identity Protection PIN, the IRS recommends you use the Get An IP PIN tool in order to protect your tax account from tax related identity theft. The IP PIN authenticates you as the valid filer of the return.
See this IRS webpage for additional steps you can take to protect your identity.