What the IRS says: “The IRS is questioning the withholding or refundable credits claimed on your return and proposes to change them unless you respond.” Here’s what it actually means, your deadline, and exactly how to respond.
The 4800C fires when claimed withholding or credits don't match employer/payer filings. It proposes reducing your refund (or increasing tax) — but unlike an audit, it resolves entirely on paper: send the W-2s, 1099s, or corrected forms that prove your numbers and the proposal is dropped.
Notice family: Underreporter & Audit — The IRS thinks your return doesn't match its records — or wants to examine it. These notices carry hard response deadlines, and a written response with documentation is exactly how they get resolved.
30 days — from the notice date to dispute the proposed change.
Counted in calendar days from the notice date. The exact respond-by date printed on your notice always controls — check page 1.
Compare the notice's figures with your physical W-2s/1099s
Respond by the deadline with copies of every form showing withholding
If an employer under-reported: get a W-2c started and say so in your response
No response = the IRS's lower figures become final
A response letter itemizing each withholding source, with the form copies attached, is normally enough. Silence converts the proposal into an assessment.
Describe the notice and your side of it — use placeholders, never your SSN or account numbers (the letter keeps [YOUR NAME]-style fields so you fill in the real details privately before mailing). A mail-ready draft with an enclosure checklist comes back in ~20 seconds.
Your IRS response letter draft will appear here.
The IRS is questioning the withholding or refundable credits claimed on your return and proposes to change them unless you respond. In practice: The 4800C fires when claimed withholding or credits don't match employer/payer filings. It proposes reducing your refund (or increasing tax) — but unlike an audit, it resolves entirely on paper: send the W-2s, 1099s, or corrected forms that prove your numbers and the proposal is dropped.
You generally have 30 days — from the notice date to dispute the proposed change. The respond-by date printed on your own notice always controls.
A response letter itemizing each withholding source, with the form copies attached, is normally enough. Silence converts the proposal into an assessment.