IRS Help Center
IRS Notice Decoder: Find Out What Your Notice Means
Updated
The IRS sends millions of notices and letters every year, each with its own code. Use this decoder to match the number on your letter to a plain-English guide, so you know what it means, how long you have to respond, and the smartest next move.
Start here: every IRS notice has a code printed in the top-right corner (such as CP14 or LT11). Find yours in the list below to learn what it means, your deadline to respond, and exactly what to do next.
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Balance Due & Reminders
Your first IRS notices about an unpaid balance. These aren't urgent enforcement yet, but the clock and the penalties are already running — handle them early to keep costs down.
- CP14 — Balance Due (your first bill)
- CP501 — Reminder of Balance Due
- CP503 — Second Reminder of Balance Due
- CP71 — Annual Balance Due Reminder
- CP71C — Annual Reminder With Passport Warning
Intent to Levy (urgent)
These notices warn that the IRS is preparing to seize wages, bank accounts, or other assets. Most carry a 30-day deadline and your right to a Collection Due Process hearing — act fast.
- CP504 — Notice of Intent to Levy
- CP90 — Final Notice of Intent to Levy
- LT11 — Final Notice of Intent to Levy
- Letter 1058 — Final Notice of Intent to Levy
- CP297 — Final Notice of Intent to Levy (Business)
Social Security & Passport
When tax debt threatens benefits or travel. These notices involve levies on Social Security payments or certification of "seriously delinquent" debt to the State Department.
- CP91 — Intent to Levy Social Security Benefits
- CP508C — Passport Certification of Seriously Delinquent Debt
Underreported Income (CP2000 series)
The IRS's records don't match what you reported. These proposed changes aren't a bill or an audit — but ignoring them can turn into one, so respond by the deadline.
- CP2000 — Proposed Changes From Underreported Income
- CP2501 — Income Discrepancy Notice
- CP2566 — Return Created For You (no return filed)
Notice of Deficiency (90-day letter)
The formal step before the IRS assesses extra tax. This is your one chance to petition the U.S. Tax Court — the 90-day deadline cannot be extended.
Federal Tax Lien
When the IRS makes a public legal claim against your property. A lien can affect your credit, your home, and your ability to sell or borrow.
Math Error & Account Changes
The IRS adjusted your return — a correction, a recalculation, or a change to your balance or refund. Check the math; you can dispute it if it's wrong.
- CP11 — Balance Due From a Math Error
- CP12 — Refund Adjusted by a Correction
- CP22A — Account Change From Your Amended Return
- CP21B — Refund From an Account Change
Refund Holds & Reviews
Your refund is delayed, applied to a debt, or under review. These notices explain why and what, if anything, you need to send.
- CP05 — Refund Held for Review
- CP49 — Refund Applied to Tax You Owe
- CP75 — Audit of Credits (EITC/ACTC verification)
Unfiled / Missing Returns
The IRS shows a return it expected but hasn't received. Filing the missing return is almost always cheaper than letting the IRS file one for you.
- CP59 — You Didn't File a Tax Return
- CP516 — Reminder of an Unfiled Return
- CP518 — Final Reminder of an Unfiled Return
- CP63 — Refund Held Until You File
- CP88 — Refund Held Due to a Missing Return
- CP80 — Credit on Account, Missing Return
Installment Agreement
For taxpayers already on a payment plan. These notices confirm a plan or warn that one is about to default — and defaulting can restart collections.
A Revenue Officer Is Involved
When the IRS assigns a person to your case. A revenue officer means your account has escalated beyond automated collections.
Don't see your notice? Browse the full IRS Help Center or call us — we read these letters every day and can tell you what yours means in minutes.
Clarity Tax Relief is not affiliated with the IRS or any government agency. Our guides are general information, not tax or legal advice for your specific situation; eligibility for IRS programs depends on individual facts and circumstances, and no outcome is guaranteed.
Related: Tax Relief Services · IRS Help Center.
Frequently asked questions about IRS notices
How do I find out what my IRS notice means?
Every IRS notice carries a code in the upper right corner — a CP number, or an LT or Letter number. That code, not the wording of the letter, identifies what the notice is and what deadline attaches to it. Find your code in the sections above to see what it means and what happens next.
Which IRS notices have a deadline I cannot afford to miss?
The ones that start a legal clock. A Notice of Deficiency gives you 90 days to petition the United States Tax Court. A final notice of intent to levy gives you 30 days to request a Collection Due Process hearing. Missing those dates does not end every option, but it does remove the specific right that notice was offering you.
Does an IRS notice mean I am being audited?
Usually not. Most notices are automated: a balance due, a math error adjustment, a reminder, or a document matching notice generated when a form the IRS received does not match what was reported on the return. An actual examination arrives as its own letter and says so plainly.
What should I do if the IRS is right but I cannot pay?
Respond anyway, before the date on the notice. Whether you owe the balance and how you pay it are two separate questions. Acknowledging the balance while you arrange a payment plan, a penalty request or hardship status keeps the account from escalating while that is being worked out.
Can I ignore a notice if I already sent the IRS a payment or a reply?
It is safer to check than to assume. IRS notices are generated on a schedule, so one can be printed and mailed before a payment or a letter you sent has been processed. Confirming that the account actually reflects what you sent is what tells you whether the notice has been overtaken by events.
What are the deadlines once the IRS moves to levy?
| Stage | What the rule is | Why it matters |
|---|---|---|
| Notice of Federal Tax Lien filed | Letter 3172 gives you 30 days to request a Collection Due Process hearing | Requested on Form 12153 |
| Bank levy served | The Internal Revenue Code provides a 21-day waiting period for complying with the levy | Time to contact the IRS and arrange to pay the tax, or notify the IRS of errors in the levy |
| Wage levy served | Part of your wages is sent to the IRS each pay period | It continues until you make other arrangements, the overdue tax is paid, or the levy is released |
| Exempt wages | Part of your wages may be exempt and is paid to you | The IRS mails Publication 1494 with the levy so your employer can work out the exempt amount |
Figures from IRS, Collection Due Process FAQs · IRS, Information about bank levies · IRS, Information about wage levies.
“Letter 3172 gives you 30 days to request a Collection Due Process (CDP) hearing to discuss the lien filing.”
— IRS, Collection Due Process FAQs
The passage quoted above is from IRS, Collection Due Process FAQs.