More than 1 million Individual Tax Identification Numbers will expire at the end of this year, the IRS warns.

The service is completing the ongoing expiration of ITINs assigned prior to 2013. Under the PATH Act, ITINs that have not been used on a federal return at least once in the last three consecutive years and those issued before 2013 will expire.

This year, ITINs with middle digits 88 will expire Dec. 31. ITINs with middle digits 90, 91, 92, 94, 95, 96, 97, 98 or 99, and that were assigned before 2013 (and have not already been renewed), will also expire at the end of the year.

Taxpayers whose ITINs are expiring and who expect to have a filing requirement in 2021 must submit a renewal application. ITINs with the middle digits 88, 90, 91, 92, 94, 95, 96, 97, 98 or 99 need to be renewed even if the taxpayer has used them in the last three years. The IRS will begin sending the CP-48 Notice to affected taxpayers in late summer.

ITINs with middle digits 83 through 87 expired last year. Middle digits 73 through 77, 81 and 82 expired in 2018. Middle digits 70, 71, 72 and 80 expired in 2017, and 78 and 79 expired in 2016. Taxpayers with these ITINs who expect to have a filing requirement in 2021 can renew at any time.

Taxpayers with an expiring ITIN can renew the numbers 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 numbers together, even if family members have an ITIN with middle digits that have not been identified for expiration. Family members include the tax filer, spouse and any dependents claimed on the return.

To renew an ITIN, a taxpayer must complete a W-7.

The IRS has ITIN information in seven languages, including English, Spanish, Chinese, Russian, Vietnamese, Korean and Haitian/Creole.