Every IRS notice carries a code, usually in the upper right corner of the first page. This page translates the codes we see most often into one-line meanings and links to a fuller guide where we have one. The meanings below are summaries of the IRS's own descriptions. Your notice, not this table, tells you the amounts, the tax year and the date you must act by.
CP notices and Letters, in number order
| Number | What it generally means | Guide |
|---|---|---|
| CP01 | The IRS confirmed an identity theft claim and added a protective indicator to your account. You will need an Identity Protection PIN to file. | See the identity theft overview |
| CP05, CP05A | Your return is under review before a refund is released; CP05A asks for documents. | CP05 and CP05A |
| CP11 | The IRS corrected your return and you now owe a balance. | CP11 |
| CP12 | The IRS corrected your return and your refund changed or you now have a refund. | CP12 |
| CP13 | The IRS corrected your return and the balance is zero. | How to read a notice |
| CP14 | You owe tax. This is usually the first bill. | CP14 |
| CP22A | The IRS changed your return and you owe a balance. | CP22A |
| CP23 | Estimated tax payments on your return did not match IRS records, and you owe. | CP23 |
| CP24 | Estimated tax payments did not match IRS records, and you have a credit. | CP24 |
| CP45 | The IRS could not apply your overpayment to next year's estimated tax as you asked. | Estimated taxes |
| CP49 | The IRS used all or part of your refund to pay a tax debt. | CP49 |
| CP59, CP515, CP518 | The IRS has no record of a prior-year return. | Unfiled return notices |
| CP71 | A reminder of an unpaid balance that needs immediate attention. | CP71 |
| CP75 | Your return is being audited and the IRS needs documents for credits or filing status. | CP75 |
| CP79 | A past audit disallowed certain credits, so you must show eligibility (Form 8862) before claiming them again. | CP75 and CP79 |
| CP87A | Another return claims a dependent with the same Social Security number. | CP87A |
| CP90, CP297 | Final notice of intent to levy and your right to a CDP hearing. | CP90 and CP297 |
| CP90C, CP297A | The IRS has already levied, and you may request a hearing afterward. | CP90 and CP297 |
| CP92, CP242 | The IRS levied your state tax refund. | Levy overview |
| CP136 | Your Form 941 deposit schedule may change for next year. | CP136 |
| CP161 | A business balance-due notice. | CP161 |
| CP162, CP162A, CP162B, CP162C | A penalty for a late, incomplete or not-electronically-filed partnership or S corporation return. | CP162 series |
| CP215 | The IRS charged a civil penalty. | Penalty types |
| CP250A | Your annual employment tax filing requirement changed, so you must file Form 941 instead of Form 944. | Form 941 |
| CP259 | A business has not filed a required return (such as Form 940, 941 or 1120). | CP259 |
| CP262, CP265 | Your S corporation election was revoked or terminated. | CP262 and CP265 |
| CP501 | First reminder that you still owe. | CP501 |
| CP503 | Second reminder that you still owe. | CP503 |
| CP504 | Notice of intent to levy, including your state refund. | CP504 |
| CP523 | You defaulted on an installment agreement. | CP523 |
| CP566 | The IRS needs more information to process your ITIN application. | CP566 |
| CP575 | Your Employer Identification Number was assigned or confirmed. | CP575 |
| CP2000 | Income, payments or credits on your return do not match third-party reports. | CP2000 |
| CP2005 | The IRS accepted your information and closed its review, with no change. | CP2000 |
| CP2100, CP2100A | A payer filed information returns with missing or mismatched taxpayer numbers. | CP2100 |
| CP2501 | An early inquiry about a mismatch, before any proposed change. | CP2000 |
| CP3219A, CP3219N | A statutory notice of deficiency (90-day letter). | CP3219A |
| CP5071 series, Letter 5071C | Identity and return verification, with an online option. | Letter 5071C |
| Letter 525, Letter 915 | A 30-day letter showing proposed audit changes. | Letter 525 |
| Letter 566 series | An audit letter asking you to support items on your return. | Letter 566 |
| Letter 531, Letter 3219 | A notice of deficiency after an audit. | CP3219A |
| Letter 692 | A letter with a computation report of proposed adjustments. | Letter 692 |
| Letter 1058, LT11 | Final notice of intent to levy and your right to a hearing. | LT11 and Letter 1058 |
| Letter 1153 | A proposed trust fund recovery penalty. | Letter 1153 |
| Letter 3172 | A federal tax lien was filed and you may request a hearing. | Letter 3172 |
| Letter 4883C, Letter 5747C | Identity verification by phone or in person. | Letters 4883C and 5747C |
| Letter 6419, Letter 6475 | 2021 advance Child Tax Credit and third stimulus payment summaries. | Letter 6419 |
If your number is not here
Search the IRS notices and letters page by number or topic. The IRS lists the number in the right corner of the letter. If it cannot be found there, treat the letter with caution and check it using the steps in our scam guide. If it is genuine but unclear, send it to us.
How we can help
We can identify the notice, check the figures against your return and IRS transcripts, and prepare a response. With a signed Form 2848, we can also speak with the IRS for you. If a deadline is close, say so when you contact us. See our IRS representation services or contact us.
Frequently asked questions
Does the number tell me how serious the notice is?
Not by itself. Look at the heading, the response date and whether the notice mentions a levy, lien, audit or deficiency. Those words indicate higher stakes.
What is the difference between a CP notice and a Letter?
CP notices are generally produced by IRS computer systems from your account or return, while letters are often more tailored. The label does not tell you how urgent a notice is. Its content and its dates do.
I have two notices for the same year. Do I respond to both?
Read each one. They may relate to different steps in the same case, such as a CP2000 followed by a notice of deficiency. Follow the instructions and dates on each.
My notice number is not in your table. What should I do?
Check it on the IRS notices and letters page, confirm the notice is genuine, and contact a tax professional if the meaning or the deadline is unclear.
Official sources
- IRS: Understanding your IRS notice or letter
- IRS: Letters and notices offering an appeal opportunity
- IRS: Notices for past due tax returns
- IRS: Topic no. 651, Notices - what to do
This page is a plain-language summary. The official source controls if there is any difference.
General information only, not tax, legal or accounting advice for your situation. Rules, limits and deadlines change; confirm the current rules with the official source or a qualified professional before you act. Reading this page does not create a professional relationship with CPA Tax Payroll and Accounting Corp.