Tax problems / CP2000
IRS Notice CP2000: proposed changes to your return.
A CP2000 comes out of the Automated Underreporter program. A computer compared the income reported on your return against the W-2s, 1099s, K-1s, and other forms filed by third parties, found a mismatch, and proposed what the tax would be if the return were wrong and the third-party forms were right. That second assumption is often the weak one.
What it means
Reading the notice
It is a proposal, and it is machine-generated
No person reviewed your return before this letter went out. The system matched information returns against your filing, found income it could not account for, and calculated tax on it. That makes it a starting position, not a determination, and it is corrected far more often than people assume.
The proposed tax is frequently too high
The computer sees gross amounts and nothing else. A brokerage 1099-B reports proceeds, so an unreported stock sale shows up as if the entire sale price were gain, with no cost basis. A 1099-NEC shows revenue with no business expenses against it. A retirement distribution that was rolled over within 60 days looks like taxable income. Supplying the missing side of the transaction commonly reduces the balance sharply, and sometimes to nothing.
It is not an audit
An examination looks at your records. This looks at a mismatch between two filings. The distinction matters because the response is narrower: you are answering one identified discrepancy, not opening your return generally. Responding well keeps it that way.
The deadline on the notice is the one that counts
The response date is printed on the notice, generally 30 days from the notice date, and 60 days if it was sent to an address outside the United States. If more time is needed, it can usually be requested, but it has to be requested rather than assumed.
What happens if you do not answer
The IRS issues a Notice of Deficiency, often numbered CP3219A, which gives 90 days to petition the Tax Court. After that window closes the tax is assessed and the only remaining routes are paying and claiming a refund, or entering the collection process. The easy stage is now.
The next 30 days
What to do, in order.
- Identify each itemMatch every proposed change to a specific third-party form.
- Find the other sideCost basis, expenses, rollovers, or the return where it was reported.
- Complete the responseAgree, partially agree, or disagree, with documentation attached.
- Track itConfirm receipt and follow the case until a closing letter arrives.
Common triggers
What usually causes one
Securities sales reported without basis
The single most common cause. Brokers report proceeds, and where basis was not reported to the IRS, or where the sale was omitted entirely, the whole proceeds figure is treated as income. Digital asset transactions increasingly produce the same result, often with basis that the exchange never had.
Forms that arrived late or never arrived
Corrected 1099s issued after filing, K-1s from a partnership that filed on extension, and forms sent to an old address all produce mismatches on returns that were correct when prepared.
Retirement distributions that were not really distributions
A rollover completed within 60 days, a trustee-to-trustee transfer, or a return of excess contribution can all show up on a 1099-R as taxable. The paperwork proving what actually happened resolves them.
Income reported in the wrong place
Income that was in fact reported, but on a different line, schedule, or entity return, is a frequent cause. The tax was paid; the matching program could not find it. The response here is documentary rather than substantive.
Identity theft and mistaken forms
Sometimes the third-party form is simply not yours, or reports income you never received. That is handled differently, through the payer and, if necessary, the IRS identity theft process, and it should not be conceded by paying.
This page is general information about how the rules work, not tax or legal advice for a specific situation. Facts change outcomes. Talk with the firm before acting on anything here.
Questions
Common questions
Do I have to pay what the CP2000 says?
No. It is a proposal. If you disagree, you respond with an explanation and documentation, and the proposed amount changes or disappears. Paying it is an option only if you agree, and agreeing to a figure calculated without your cost basis or expenses is usually paying too much.
I sold stock and forgot to report it. Do I owe tax on the whole sale price?
Almost never. You owe tax on the gain, which is proceeds less your cost basis. The notice shows the whole proceeds because the IRS was not given the basis. Supplying purchase records, and the holding period that determines the rate, typically reduces the proposed tax dramatically and sometimes produces a loss.
Should I file an amended return in response?
Usually not as the first step. The CP2000 has its own response form and process, and filing an amended return alongside it frequently causes the two to cross and confuse the case. There are situations where an amended return is the right tool, and they are worth identifying before filing anything.
Will there be a penalty as well as the tax?
Often an accuracy-related penalty of 20 percent of the understatement is proposed alongside the tax. Where the underlying adjustment is reduced, the penalty falls with it, and the penalty itself can be challenged separately on reasonable cause or eliminated if the adjustment goes away.
I never got the notice and now the IRS says I owe. What now?
That happens with address changes. The path forward depends on what stage the case reached: reconsideration of the assessment is available in many cases, and audit reconsideration or an amended return may apply. It is more work than answering on time, but it is not a dead end.
Answer the discrepancy, not the number.
Send us the notice and the return. Most of these are resolved by supplying what the IRS could not see, and the difference between a good response and a late one is usually thousands of dollars.