Economic Impact Payment: Taxpayers will receive IRS Letter 6475 if they receive the 3rd round of Economic Impact Payment or the “plus-up” payments for 2020 Income. You will need this letter for your 2021 tax return.
Child Tax Credit: Taxpayers will receive IRS Letter 6419 if they receive payments for the July – December 2021 period. This letter is required to reconcile payments made to you and remaining credits. If taxpayer did not keep the letter, a copy may be obtain from https://www.irs.gov/credits-deductions/child-tax-credit-update-portal.