The Internal Revenue Service has begun mailing letters to more than a million taxpayers who have Individual Taxpayer Identification Numbers (ITINs) that will expire at the end of the year. The IRS is urging recipients to renew their ITINs as quickly as possible to avoid delays associated with their returns.

The renewals affect ITINs with middle digits of 70, 71, 72, or 80. These will expire Dec. 31, 2017. Taxpayers with expiring ITINs will receive a CP-48 Notice that explains the steps needed to renew in order to use the ITIN in 2018.

“We urge people who receive this letter to renew their ITIN as quickly as possible to avoid tax refund and processing delays next year,” said IRS Commissioner John Koskinen. “Taking steps now and renewing early will make things go much more smoothly for ITIN holders when it comes time to file their taxes.”

ITINs with middle digits 78 and 79 that expired at the end of last year can be renewed at any time.

Who Should Renew an ITIN?

Taxpayers with ITINs set to expire and who need to file a tax return in 2018 must submit a renewal application. Others do not need to take any action.

• ITINs with middle digits 70, 71, 72, or 80 (For example: 9NN-70-NNNN) need to be renewed if the taxpayer will have a filing requirement in 2018.
• Taxpayers whose ITINs expired due to lack of use should only renew their ITIN if they will have a filing requirement in 2018.
• Taxpayers who are eligible for, or who have, an SSN should not renew their ITIN, but should notify IRS both of their SSN and previous ITIN, so that their accounts can be merged.
• Taxpayers whose ITINs have middle digits 78 or 79 that have expired should renew their ITIN if they will have a filing requirement in 2018.
• Taxpayers with an ITIN with middle digits 70, 71, 72, 78, 79, or 80 have the option to renew ITINs for their entire family at the same time. Those who have received a renewal letter from the IRS can choose to renew the family’s ITINs together even if family members have an ITIN with middle digits other than 70, 71, 72, 78, 79, or 80.

ITINs are used by taxpayers who must file a tax return or otherwise report income under U.S. law, but aren’t eligible for a Social Security Number. The IRS recommends current ITIN holders visit the IRS information page and review the guidelines.