An envelope from the IRS can ruin your afternoon. But most IRS letters are routine. They might ask a question, explain a change to your refund, or point out a mismatch you can clear up with a few documents. The letters that turn into real problems are usually the ones that sat unopened.
Here's a calm, step-by-step way to handle one.
Step 1: Don't panic, and open it
The IRS sends notices for many reasons, including a balance due, a change to your refund, a question about your return, or a request to verify your identity. Read the whole letter before you do anything. It will tell you what the IRS thinks happened, what it wants from you, and by when.
Step 2: Find the notice number
Every IRS notice has an identifying number. The IRS says you can find "the CP or LTR number on the right corner of the letter." That number tells you what kind of letter it is, and IRS.gov has a plain-English page for most of them. Here are some common ones:
| Notice | What it means |
|---|---|
| CP2000 | Income or payment information from third parties (employers, banks, brokers) doesn't match your return. The IRS proposes changes. It is not a bill. |
| CP11 | The IRS corrected one or more mistakes on your return, and the amount you owe changed. |
| CP12 | The IRS corrected one or more mistakes, and you're now due a refund or your refund amount changed. |
| CP14 | You owe money on unpaid taxes. |
| CP501 | A reminder that you still owe a balance. |
| CP503 | The IRS hasn't heard from you and you still have an unpaid balance. |
| CP504 | Notice of intent to levy. If you don't pay, the IRS can levy income and bank accounts, seize property, and take your state tax refund. |
| Letter 525 | A "30-day letter" after an audit by mail. It proposes changes and usually includes Form 4549 showing them. |
CP14, CP501, CP503 and CP504 often come in sequence when a balance goes unpaid. Each step gets more serious, so the earlier you respond, the more options you have.
Step 3: Make sure it's really from the IRS
Scammers impersonate the IRS all the time. The IRS says it "initiates most contacts through regular mail delivered by the United States Postal Service." It will never:
- Call to demand immediate payment using a specific method such as a prepaid debit card, gift card or wire transfer,
- Threaten to have you arrested or deported, or to revoke your license, or
- Skip mailing you a bill before calling about taxes you owe.
To check a letter, compare its notice number to the IRS's notice pages. If something seems off, call the IRS at 800-829-1040 using that number, not a number printed in a suspicious letter. You can also sign in to your IRS online account to see your balance and, in many cases, your notices. Report phone scams to the Treasury Inspector General for Tax Administration (TIGTA) at 800-366-4484, and forward phishing emails to phishing@irs.gov.
Step 4: Note the deadline
Every notice that needs a response gives a date. Put it in your calendar right away. Deadlines vary by notice, so go by what your letter says:
- For a CP2000, reply by the date listed on the notice.
- For a CP11, if you disagree you must contact the IRS by the date shown. If you miss it, you lose your formal right to have the change reversed and your right to appeal.
- For a Letter 525, you generally have 30 days from the date of the letter to request a conference with the IRS Independent Office of Appeals if you disagree.
If you owe and can't pay in full, pay what you can by the deadline. Even a partial payment reduces the interest and penalties that keep building. Then look into a payment plan, which you can often set up online.
Step 5: Decide whether you agree
If you agree
Follow the instructions on the notice. For a CP2000, if you agree with the proposed changes and have nothing else to report, you generally don't need to file an amended return. Sign and return the response form and pay or set up a payment arrangement as directed.
If you disagree
Respond in writing by the deadline. Explain why and include copies (never originals) of your supporting documents, such as a corrected 1099, a brokerage cost-basis statement, or receipts. Here's a common example: a CP2000 says you didn't report $20,000 from a stock sale. In fact, you reported the sale but the cost basis wasn't on the form, so the IRS treated the whole amount as gain. A brokerage statement showing what you paid can resolve it.
Keep a copy of everything you send, and use a mailing method that gives you proof of delivery.
Step 6: Get representation if you need it
You don't have to deal with the IRS alone. Form 2848, Power of Attorney and Declaration of Representative, lets you authorize someone eligible to practice before the IRS, such as an attorney, CPA or enrolled agent, to represent you. Once it's on file, your representative can see your confidential tax information and talk to the IRS for you.
If your tax problem is causing financial hardship, or you've tried normal IRS channels without success, the Taxpayer Advocate Service may help. It's an independent organization within the IRS, and its help is free. You can reach it at 877-777-4778 or through taxpayeradvocate.irs.gov.
When it's worth getting help
A CP12 with a small refund change may need no action at all. Get professional help if you've received an audit letter or a Letter 525, a CP504 or other collection notice, a CP2000 with a large proposed amount, or letters covering several years. It's also worth it if you simply don't understand what the IRS is asking. If you're behind on filing, see what to do if you're filing late. To lower the chance of future letters, read avoiding IRS red flags.
Our CPAs and Enrolled Agents can review your notice, respond for you under a Form 2848, and handle follow-up through our audit representation service. Book an appointment and bring the letter with you.
Sources
- IRS: Understanding your IRS notice or letter
- IRS: Understanding your CP2000 series notice
- IRS: Understanding your CP11 notice
- IRS: Understanding your CP12 notice
- IRS: Understanding your CP14 notice
- IRS: Understanding your CP501 notice
- IRS: Understanding your CP503 notice
- IRS: Understanding your CP504 notice
- Taxpayer Advocate Service: Letter 525
- IRS: How to know it's really the IRS calling or knocking on your door
- IRS: About Form 2848, Power of Attorney and Declaration of Representative
- IRS: The Taxpayer Advocate Service is your voice at the IRS
General information, not tax advice. Tax rules change and depend on your situation. Figures are for tax year 2026 unless noted; confirm current amounts at IRS.gov or talk to a Stellar Tax professional before acting.