CP2000 notice: what it means and what to do

A CP2000 is not a bill and it is not an audit. It is a proposed change to your tax return, generated automatically because income reported to the IRS by someone else does not match what appeared on your return. You have 30 days to respond, and the amount printed on it is frequently wrong.

If you are reading this late at night with the notice in front of you, that paragraph is the important part. Nothing is being collected. Nothing has been decided. You are being asked a question and given a month to answer it.

What is a CP2000 notice?

It comes from the IRS Automated Underreporter programme. Every year, employers, banks, brokerages, retirement plan administrators and clients file information returns about you. A computer compares that pile of documents against the return you filed. When something does not line up, it generates a CP2000 setting out the difference and calculating what the tax would be if the IRS assumption is correct.

No person examined your return. Nobody decided you looked suspicious. A mismatch was flagged, a letter was produced, and it was posted.

The most common causes, in roughly the order I see them:

• Stock or fund sales where the cost basis was missing. Your broker reported that you sold $40,000 of shares. If your return did not show what you paid for them, the IRS treats the entire $40,000 as profit. This is the single most frequent reason for a large and alarming CP2000.
• A 1099 you forgot about. Freelance work, a side project, interest from an account you rarely use, a small dividend.
• A retirement account rollover reported as a distribution. You moved money from one account to another, the plan reported it as a withdrawal, and nothing on your return explained that it was rolled over.
• Income belonging to someone else with a similar name or a mistyped Social Security number.
• A corrected form issued after you filed, which you never saw.

What is the IRS actually saying?

Roughly this: “Someone told us about income we cannot find on your return. If we are right, here is what you would owe. Tell us whether we are right.”

That is genuinely the whole message. The notice includes a response form with boxes for agreeing, partially agreeing, or disagreeing, because the IRS expects a meaningful share of these to be wrong.

They are frequently wrong because the IRS only ever sees one half of the transaction. They know what you sold and not what you paid. They know a distribution left your retirement account and not where it went. They can see gross receipts and not the expenses against them. Filling in the missing half is usually the entire job.

It also occasionally works in your favour. A CP2000 can result in a refund if the correction turns out to reduce your tax.

How long do I have to respond?

Thirty days from the date printed on the notice, not from the day it arrived in your letterbox. Find that date now, count thirty days forward, and write it somewhere you will see it. If you are outside the United States it is generally sixty days.

If you need longer, you can call the number on the notice and ask. Extensions are commonly granted, particularly when you are gathering documents. Asking is far better than missing the date silently.

Interest runs from the original due date of the return regardless of when you respond, so a slow reply costs a little even if you are right in the end. It is not a reason to panic, but it is a reason not to leave it in a drawer for three weeks.

What happens if I ignore it?

Nothing sudden. The sequence is slow and procedural.

If you do not respond, the IRS eventually issues a Notice of Deficiency, usually Letter 3219A. That one is different in kind and it matters. It gives you 90 days to petition the United States Tax Court, and that deadline cannot be extended for any reason at all.

If you let the 90 days pass as well, the proposed tax is assessed as though the IRS were right. From that point you are arguing against an assessment rather than a proposal, which is harder and slower, though not impossible. Collection notices begin arriving after that.

There may also be an accuracy-related penalty of 20% of the understated tax where the amount is substantial. Responding promptly and reasonably is the best protection against it.

What are my options?

Agree. If the IRS is right, sign the response form and return it. If you can pay, pay. If you cannot pay, still send the form back and deal with the balance separately. Agreeing and not paying is a manageable situation. Not responding is the one that gets worse.

Partially agree. Common and completely normal. Perhaps you did miss a 1099, but the stock sale they have valued at $40,000 of profit actually cost you $37,000. Tick the partial box, explain the part you dispute, and attach the evidence.

Disagree. Write a clear explanation and attach documents that support it. Brokerage statements showing what you paid. A Form 5498 or account statement showing a rollover was completed. An invoice log. A corrected 1099. Keep it short, be specific, and reference the item numbers used on the notice.

Whichever applies, send it the way the notice tells you to and keep a complete copy of everything. If there is a fax number on the notice, faxing is usually faster and gives you a transmission record. Processing can still take a couple of months, and the silence afterwards is normal rather than ominous.

Should I file an amended return instead?

Usually not, and this is the most common mistake people make with a CP2000. The notice is not asking you to amend. It is asking you to respond to it, using the form it came with.

Filing a Form 1040-X on its own often makes things worse, because the amended return and the notice then travel through two different parts of the IRS at two different speeds and neither one closes the other out. People end up with a resolved amendment and an unresolved notice, or duplicate assessments.

There are situations where an amended return is attached to the response, particularly where the correction affects other parts of the return. But it goes with the response rather than instead of it.

Do I actually need help with this?

Often, no, and I would rather tell you that than take your money.

You can almost certainly handle it yourself if the notice concerns one forgotten 1099, the IRS is right, the amount is small enough that you can pay it, and you have no other tax years outstanding. Sign the form, send it back, pay the balance. That is an evening’s work and you do not need anyone.

It is worth having someone when the amount is large enough to matter, when you need to prove the IRS figure is wrong rather than simply accept it, when the notice involves stock sales and missing basis, when you are self-employed and expenses are involved, when there are unfiled years sitting behind it, when a business or rental property is in the picture, or when you have already missed the deadline.

And if the honest reason is that you have been avoiding it and would rather hand it to somebody, that is a perfectly good reason too. Avoidance is what turns a small problem into a large one.

Other notices: LT11 and Letter 1058 · all IRS notices and audits

Michael Jones, EA & CFP®. Enrolled Agent, licensed by the U.S. Department of the Treasury to represent taxpayers before the IRS in all fifty states. This page is general information about how CP2000 notices work, not advice about your particular notice. Deadlines and penalty rates change, so check the notice itself for the dates that apply to you.