Is this about your personal tax return, not a business? A 4883C means the IRS stopped your tax return until you call and confirm you filed it. Call the number on the letter with the letter, a copy of the return and a prior-year return in hand; the IRS will not verify you without the letter. Your refund is released after the call, usually within nine weeks. If you did not file the return, tell them; the IRS treats it as identity theft. The rest of this page goes deeper, from the side of the businesses that file 1099s; the parts on how the IRS handles the letter apply to you too.
What Letter 4883C is
The telephone-only version of the Taxpayer Protection Program letter, "Issued on accounts for returns filed with an address in the United States" (IRM 25.25.6.1.7, June 15, 2026). The return the IRS received under the person's Social Security number was selected by its identity-theft models and is held unposted until the filer calls and passes authentication. Letter 5447C is the same letter for a foreign address, and Letters 6330C and 6331C were pilot versions that "cannot be reissued"; a lost 6330C is replaced by a 4883C. Nothing a payer filed caused it.
The deadline
The letter sets no response date, but the return does not process and no refund issues until the call is completed, and no transcript or account information is released while the issue is open (IRM 25.25.6.1.7). Posting after verification takes up to nine weeks.
What to do
Call the TPP number on the letter with the letter, a copy of the return in question, a prior-year return and supporting documents; the letter itself is required for phone authentication. A person who cannot pass by phone is referred to a Taxpayer Assistance Center, where the letter is not required but identification documents are. If you did not file the return, tell the assistor; the IRS marks the return as identity theft and the account is corrected without you. A caller who has lost the letter can have a replacement issued after authentication of identity.
Questions about Letter 4883C
Who receives Letter 4883C?
Individual taxpayer. The telephone-only version of the Taxpayer Protection Program letter, "Issued on accounts for returns filed with an address in the United States" (IRM 25.25.6.1.7, June 15, 2026).
What is the deadline on Letter 4883C?
The letter sets no response date, but the return does not process and no refund issues until the call is completed, and no transcript or account information is released while the issue is open (IRM 25.25.6.1.7). Posting after verification takes up to nine weeks.
What should I do when Letter 4883C arrives?
Call the TPP number on the letter with the letter, a copy of the return in question, a prior-year return and supporting documents; the letter itself is required for phone authentication. A person who cannot pass by phone is referred to a Taxpayer Assistance Center, where the letter is not required but identification documents are. If you did not file the return, tell the assistor; the IRS marks the return as identity theft and the account is corrected without you. A caller who has lost the letter can have a replacement issued after authentication of identity.
Is Letter 4883C about my own income tax?
No. This decoder covers information reporting and withholding: the notices a payer, filer or payee sees because of Forms 1099, W-2, 945 and the TINs on them. Individual income-tax notices follow a different track.
Have a different notice? The IRS notice decoder lists all 83 in the order they tend to arrive.