IRS Letter 105C: Claim Disallowed

What the IRS says: “The IRS has fully disallowed a claim for refund or credit you filed, with your appeal rights.” Here’s what it actually means, your deadline, and exactly how to respond.

Refund Holds & Unfiled ReturnsRespond promptlyDeadline: 30 daysFree response letter draft

What Letter 105C actually means

The formal 'no' to a refund claim, amended return, or credit request. Two clocks start: you can appeal within the IRS (30 days for Appeals consideration per the letter) and — the one with teeth — you have 2 years from the disallowance date to sue in district court or the Court of Federal Claims. A signed Form 2297 waives the 2-year suit right; don't sign it casually.

Notice family: Refund Holds & Unfiled Returns — Your refund is frozen or the IRS has no return on file for a year it expected one. These resolve by filing, verifying, or sending exactly the documents requested — silence makes them worse.

Your deadline

30 days — for IRS Appeals; 2 years from the notice date to file suit.

Counted in calendar days from the notice date. The exact respond-by date printed on your notice always controls — check page 1.

Why you received Letter 105C

What to do about Letter 105C

1

Step 1

Read the stated ground — statute-barred vs merits changes your options completely

2

Step 2

Merits disputes: file a written protest for IRS Appeals within the letter's window

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Step 3

Statute issues: check the mailbox rule, extensions (Form 872), and financial-disability tolling — timely claims get mislabeled

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Step 4

Diary the 2-year suit deadline as the absolute backstop

How to respond

A protest letter that attacks the specific disallowance ground — with the timeline documented (postmarks, certified receipts) for statute cases — reverses a meaningful share of these. The 2-year court window is the leverage behind every negotiation.

Draft a Letter 105C response letter now ↓

Draft your response letter

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.

Frequently asked questions

What does IRS Letter 105C mean?

The IRS has fully disallowed a claim for refund or credit you filed, with your appeal rights. In practice: The formal 'no' to a refund claim, amended return, or credit request. Two clocks start: you can appeal within the IRS (30 days for Appeals consideration per the letter) and — the one with teeth — you have 2 years from the disallowance date to sue in district court or the Court of Federal Claims. A signed Form 2297 waives the 2-year suit right; don't sign it casually.

How long do I have to respond to Letter 105C?

You generally have 30 days — for IRS Appeals; 2 years from the notice date to file suit. The respond-by date printed on your own notice always controls.

Should I respond to Letter 105C in writing?

A protest letter that attacks the specific disallowance ground — with the timeline documented (postmarks, certified receipts) for statute cases — reverses a meaningful share of these. The 2-year court window is the leverage behind every negotiation.

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