Short answer
Letter 950 is the IRS 30-day letter sent when a field audit by a revenue agent ends without agreement. It encloses the examination report and gives you 30 days from the letter’s date to sign the agreement or file a protest with the IRS Independent Office of Appeals. If you do neither, the IRS sends a notice of deficiency.
Key takeaways
- Letter 950 closes an unagreed field audit: the revenue agent’s findings are final at the exam level, and your next stop is Appeals or, later, the Tax Court.
- The response date is printed on the letter, generally 30 days from its date; extensions are discretionary and normally no more than 30 days.
- Disputes over $25,000 (IRS.gov, 2026) in tax and penalties for any period need a formal written protest; smaller ones can use a small case request.
- Ignoring the letter leads to a notice of deficiency and a fixed 90-day Tax Court deadline.
What Letter 950 is and who sends it
The IRS Independent Office of Appeals calls Letter 950 the “30-Day Letter-Straight Deficiency,” used for “un-agreed, straight deficiency, straight overassessment or mixed deficiency and overassessment cases,” and says that you “should file your protest within 30 days from the date of this letter.”
The IRS manual places it in field examination. IRM 4.10.8.12.1 (revised April 10, 2023) lists Letter 950 as the 30-day letter “for straight deficiency, or mixed deficiency and overassessment cases in Field Examination.” Field audits, done by revenue agents, start with Letter 2205 or 2205-A. Office audits end with Letter 915 instead, and mail audits with Letter 525 (see the audit letter lookup).
Related versions in the manual:
| Letter | Used for (IRM 4.10.8.12.1) |
|---|---|
| Letter 950 | Unagreed deficiency, or mixed deficiency and overassessment, in a field exam |
| Letter 950-B | Unagreed reports when the taxpayer is in bankruptcy |
| Letter 950-F | Overassessments and no-change-with-adjustments cases |
| Letter 950-Z | Unagreed cases in Large Business and International (LB&I) exams |
The manual tells examiners to hand 30-day letters over in person where they can, with a copy to your representative if a Form 2848 is on file.
Why you got it
You get a Letter 950 because the revenue agent proposed changes and you did not agree to all of them. Publication 3498 (Rev. 5-2025) says that if you and the examiner “don’t reach an agreement, you will receive a letter (known as a 30-day letter).”
It is not a bill or a notice of deficiency; nothing has been assessed. It is your last chance to dispute the findings inside the IRS without a court filing.
If fewer than 240 days remain on the assessment statute, the manual says you get Letter 5153 instead, which “is not a 30-day letter”: it asks you to extend the statute within 10 days. Sign, and a 30-day letter follows; don’t, and the case goes to a notice of deficiency.
What comes with Letter 950
IRM 4.10.8.12.1 says a 30-day letter must include “a complete examination report” with the explanations of each issue and a waiver where required, plus Publication 3498, which “must always be enclosed.” In practice, for an individual field audit, expect:
- Form 4549-A, Income Tax Discrepancy Adjustments. The manual’s table of unagreed report forms pairs Form 4549-A with Form 870 for individual (1040) and corporate (1120) returns.
- Form 870, the waiver of restrictions on assessment and collection. Signing it is how you agree.
- Lead sheets, one per issue. In field exams, the manual says “a copy of the examiner’s lead sheet relating to each issue” is attached, numbered to match the report, with four parts: Conclusion, Facts, Law and Taxpayer’s Position. LB&I examiners use Form 886-A instead.
- Publication 3498.
Read the lead sheets first: they show the facts and code sections the agent relied on, and a protest that answers them point by point is far stronger than a general objection.
Your deadline and asking for more time
The date that controls is the response date printed on your letter, generally 30 days from the letter’s date. Count from the date on the letter, not the day it arrived.
Extensions exist but are not a right. IRM 4.10.8.12.8 says the procedural rules do “not provide for an extension,” but “as a matter of practice, extensions may be granted under reasonable circumstances,” such as hiring a new representative who needs time for a meaningful protest, illness, or complex issues. Requests “should be in writing” with your reasons. The group manager grants them by Letter 686 with the new date, they are “normally granted for no more than 30 days,” and they are not granted when the statute expires within 240 days unless you also extend the statute. If you live outside the United States, the manual says the letter should allow a reasonable longer period.
Publication 3498 says you can’t appeal administratively unless enough time remains on the statute when Appeals receives your case, “generally 365 days.” You may be asked to sign a consent; you can refuse, negotiate its scope or length, or sign (Publication 1035). Read our Form 872 guide before signing one.
Your options at a glance
| Option | What you send | What happens next |
|---|---|---|
| Agree with everything | Signed Form 870 (and payment if you can) | The case closes as agreed; the tax is assessed and billed. No notice of deficiency for those items. |
| Agree in part | A partial agreement for the items you accept, plus a protest for the rest | The manual says the agreed part is processed and a new 30-day letter issues for the remaining issues if time allows. |
| Send new facts | Documents or an explanation to the agent | If the report doesn’t change or goes down, you may get Letter 692 asking you to agree within 15 days; if new issues arise or the amount rises, a new 30-day letter. |
| Small case request | A brief written statement or Form 12203, when each period is $25,000 or less | The case goes to Appeals. |
| Formal written protest | A protest with all the items Publication 5 requires | The group reviews it, may add a rebuttal, then sends the case to Appeals. |
| Do nothing | Nothing | The case goes to Technical Services for a notice of deficiency. |
Publication 5 also lets you ask for a talk with the agent’s supervisor, or for Fast Track Settlement if you qualify. Our agree-or-appeal guide walks through the decision, and the 30-day letter guide covers what signing means.
How to respond to Letter 950
- Mark each adjustment on Form 4549-A agree or disagree, with the record or rule that supports you.
- Check the amount per period. Add the proposed tax and penalties for each year in the letter. If every period is $25,000 or less, a small case request is enough; if any one is more, Publication 5 requires a formal protest.
- Write the protest. Publication 5 requires your name, address and daytime phone; a statement that you want to appeal; a list of every disputed issue, the tax periods, the proposed changes and why you disagree with each; the facts; any law or authority you rely on; and a signed penalties-of-perjury statement. Our formal protest template follows that list.
- Sign the right declaration. If a representative prepares and submits it, the manual says they use a substitute declaration. Publication 5 gives two versions, one for a representative with personal knowledge of the facts and one without.
- Send it to the address on the letter, not to Appeals. Keep a full copy and proof of mailing or delivery; a cover letter listing each enclosure helps.
- Watch for follow-up letters. Letter 1025 returns an incomplete protest for fixing; Letter 5072 sends you the agent’s rebuttal; Letter 2280 says the case has gone to Appeals.
The manual says a protest that cites a code section but gives no reasons or facts is inadequate, and so is one that disagrees only because you can’t pay.
What happens next
If you protest: the case goes to Appeals, which is independent of the exam team and contacts you to set a conference. See how Appeals works.
If you don’t respond: the manual says that if you said you intended to protest but didn’t, the examiner should send Letter 923 as a reminder within seven days after the deadline. After that, a deficiency case is closed “to Technical Services for issuance of a notice of deficiency.” Publication 3498 confirms the result: a “90-day letter, also known as a notice of deficiency.” For an in-person audit this is usually Letter 531.
Under IRC 6213(a), you then have 90 days from the mailing of that notice (150 days if it is addressed to a person outside the United States) to petition the U.S. Tax Court. Read notice of deficiency: your Tax Court deadline. Interest runs throughout at the federal short-term rate plus 3 percentage points, reset quarterly (7% (IRS.gov, Jul-Dec 2026) this quarter); if you can’t pay, see options when you can’t pay an audit bill.
Mistakes to avoid
- Signing Form 870 to make it go away. Signing waives the restrictions on assessment for those items, so they never reach a notice of deficiency or prepayment Tax Court review.
- Saving your best evidence for Appeals. Publication 5 says new information sent to Appeals may first go back to the IRS employee, which “will likely delay” your case. Give it to the agent now.
- Sending an unlabeled payment. Without a signed agreement, the manual says a payment is not treated as an IRC 6603 deposit unless you designate it. Say which you intend in writing.
Field audits often involve a business or several years, where a representative adds the most. You can still respond yourself; Low Income Taxpayer Clinics help eligible taxpayers for free or a small fee; the Taxpayer Advocate Service (877-777-4778 (IRS.gov, 2026)) helps when an IRS problem is causing hardship. If you want a second opinion on the report, request a free review or call 1-877-800-8180. Global Gate Tax Relief’s team includes licensed tax attorneys, enrolled agents and CPAs; if it takes the case, it quotes a flat fee upfront and does not promise an outcome.
Frequently asked questions
It is the 30-day letter the IRS sends after a field audit ends with changes you did not agree to. It encloses the report and explains how to agree or protest to Appeals within 30 days of the letter’s date.
No. Letter 950 is a preliminary letter; nothing has been assessed. The notice of deficiency (usually Letter 531 after an in-person audit) comes later if you don’t respond or don’t settle, and it starts the 90-day Tax Court deadline.
Generally 30 days from the date on the letter; the exact response date is printed on it. Ask for more time in writing before it passes; extensions are normally no more than 30 days.
Only for items you actually agree with. Signing lets the IRS assess and collect those amounts without a notice of deficiency. You can agree to part of the report and protest the rest.
The case is sent for a notice of deficiency. You then have 90 days from its mailing date (150 if addressed outside the US) to petition the Tax Court; if you don’t, the tax is assessed and billed.
Sources
- IRS Independent Office of Appeals: Letters and notices offering an appeal opportunity
- IRM 4.10.8, Report Writing (4.10.8.12, Unagreed Case Procedures)
- IRM 4.10.2, Pre-Contact Responsibilities
- IRS Publication 3498, The Examination Process (Rev. 5-2025)
- IRS Publication 5, Your Appeal Rights and How to Prepare a Protest (Rev. 4-2021)
- IRS Publication 1035, Extending the Tax Assessment Period (Rev. 9-2017)
- 26 U.S.C. 6213, Restrictions applicable to deficiencies; petition to Tax Court
- IRS: Low Income Taxpayer Clinics
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