The IRS will begin sending the CP-48 notice; You must renew your Individual Taxpayer Identification Number (ITIN) to file your U.S. tax return in late summer to taxpayers who have filed a tax return containing an ITIN with the middle digits 73, 74, 75, 76, 77, 81 or 82 in the last three years. The notice explains the steps to take to renew the ITIN if it will be included on a U.S. tax return filed in 2019. Example 999-_ _-9999