IRS Notice Library · Plain English Explanations

Got a letter from the IRS? Find it here.

Every IRS notice has a number, usually starting with "CP" or "LT," printed at the top right of the letter. Find yours in the list below to understand what it means, how urgent it is, and what to do next. If you don't see yours or you're not sure what to do, call me. That's what I'm here for.

Most IRS notices sound scarier than they actually are when you first open them. Before you panic, take a breath. Receiving an IRS notice does not automatically mean the worst-case scenario is happening. Some notices are simple requests for information. Sometimes the notice is telling you that you are due a refund. Others are more urgent. The important thing is understanding what you received and responding appropriately.

Talk to Candy: Free Consultation
Urgency Key:
ACT NOW These notices usually have important deadlines and should be addressed quickly.
REVIEW Read carefully, action may be needed
INFORMATIONAL No immediate action required

IRS Notice Reference List

Organized by category. The ✓ column means a full client explanation document is available, ask Candy for a copy.

Balance Due The IRS says you owe money and wants you to pay.
Notice # What It Means: Plain English Urgency
CP14First notice that you have an unpaid balance. The IRS is requesting payment of taxes owed plus interest and penalties.ACT NOW
CP501Second reminder, you still owe a balance. Interest and penalties continue to add up.ACT NOW
CP503Third notice, the IRS has not received payment. Collections activity is approaching.ACT NOW
CP504Final notice before levy action. The IRS intends to seize your state tax refund and may levy other assets.ACT NOW
Return Changes The IRS made changes to your tax return and you may owe more, or get more back.
Notice # What It Means: Plain English Urgency
CP11The IRS made changes to your return and you now owe a balance as a result of those changes.ACT NOW
CP12The IRS corrected your return and your refund amount has changed. Review to make sure you agree.REVIEW
CP2000The IRS received information from a third party (employer, bank, etc.) that doesn't match your return. This is a proposed change, not a final bill.ACT NOW
CP22AThe IRS made changes you requested to your return and you now owe a balance.ACT NOW
Refund Issues Something is preventing your refund from being issued or it has been changed.
Notice # What It Means: Plain English Urgency
CP05Your refund is being held while the IRS reviews your return. No action needed yet, but respond quickly if asked.REVIEW
CP05AThe IRS needs documentation to support your refund claim. You must respond with proof.ACT NOW
CP42The amount of your refund has changed because the IRS applied it to a debt owed by your spouse.REVIEW
CP53Your refund could not be sent by direct deposit and the IRS is issuing a paper check instead.INFORMATIONAL
Audit & Verification The IRS is examining your return and needs documentation.
Notice # What It Means: Plain English Urgency
CP75Your Earned Income Credit is being audited. You must send documentation to prove your eligibility.ACT NOW
CP2501The IRS received information from a third party that doesn't match your return and wants to discuss it before making changes.ACT NOW
CP3219AStatutory Notice of Deficiency, the IRS has proposed a tax increase. You have 90 days to respond or petition Tax Court.ACT NOW
Identity & Security The IRS needs to verify your identity or has flagged potential fraud on your account.
Notice # What It Means: Plain English Urgency
CP01The IRS confirmed your identity theft claim and added a protective marker to your account.INFORMATIONAL
CP01AYour Identity Protection PIN (IP PIN) is enclosed. You must use it when filing your next return.ACT NOW
Letter 5071CThe IRS needs you to verify your identity online or by phone before releasing your refund.ACT NOW
Letter 4883CThe IRS needs you to call to verify your identity before it can process your return.ACT NOW
Unfiled Tax Returns The IRS has no record of receiving your tax return for one or more years.
Notice # What It Means: Plain English Urgency
CP59First notice, the IRS has no record of your return for a specific year. File or explain why you don't owe.ACT NOW
CP88Your refund is being held because you have an unfiled return from a prior year. File the missing return to get your refund.ACT NOW
CP516Second request, the IRS still hasn't received your return. File immediately.ACT NOW
CP518IFinal notice, if you don't respond the IRS will file a Substitute for Return on your behalf, likely in their favor.ACT NOW
Credits You may be eligible for a tax credit you didn't claim.
Notice # What It Means: Plain English Urgency
CP08You may qualify for the Child Tax Credit. The IRS is letting you know you may be eligible.REVIEW
CP09You may qualify for the Earned Income Credit. Complete the worksheet enclosed and return it to claim your credit.REVIEW
CP27You may be eligible for the Earned Income Credit even though you didn't have a qualifying child. Complete the form to claim it.REVIEW
Collections & Levies The IRS is taking or planning to take collection action against you.
Notice # What It Means: Plain English Urgency
CP90Final Notice of Intent to Levy, the IRS intends to seize your wages, bank account, or other assets. You have 30 days to respond.ACT NOW
LT11Final Notice of Intent to Levy and your right to a hearing. This triggers your Collection Due Process (CDP) rights.ACT NOW
Penalties The IRS has assessed a penalty on top of taxes owed.
Notice # What It Means: Plain English Urgency
CP30The IRS is charging you an underpayment penalty because you did not pay enough estimated tax during the year.REVIEW
Payment Plans Notices related to an existing installment agreement.
Notice # What It Means: Plain English Urgency
CP521Your installment agreement payment is due. A reminder of the amount and due date.REVIEW
CP523Your installment agreement is in default. You must pay immediately or your agreement will be terminated and levy action may begin.ACT NOW

The IRS sends hundreds of different notices, and helping people understand them is a regular part of what I do.

This list covers the 31 most common notices taxpayers receive. If yours isn't listed here, or if you found yours but you're not sure what to do, that's exactly what the free consultation is for. Bring the letter. I'll tell you what it means and what your options are.

Found your notice? Let's talk about what to do next.

No charge for the first conversation. No judgment. Just honest answers.

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