IRS Help Center
IRS Notice Decoder: Find Out What Your Notice Means
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.
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.
Not Sure What Your Notice Means? We'll Read It With You.
Bring us the letter and we'll explain what the IRS is asking, what your real deadline is, and your best options — in a free, confidential consultation. No pressure, no obligation.
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.