The CP2000 notice means the IRS received information from employers, banks, or other sources showing income you didn't report on your tax return. This is called an "underreporter inquiry."
This is NOT an audit (yet). It's a proposal. The IRS is saying "We think you owe more taxes based on this information" and giving you a chance to respond.
The notice will show:
Unlike most IRS notices, the CP2000 is a proposal, not a bill. You have the right to disagree and provide evidence. Many people successfully reduce or eliminate CP2000 assessments.
You received income reported on a 1099 form (freelance work, interest, dividends) but forgot to include it on your return.
You sold stocks, crypto, or investments but didn't report the transactions. Brokers send this info to the IRS automatically.
You reported investment sales but used the wrong cost basis, making your gains look lower than they actually were.
You took money from a retirement account but didn't report it as income on your return.
If you actually didn't report this income and the amount is correct, sign the response form, pay the amount (or set up a payment plan), and return it by the deadline.
This is the fastest way to resolve it.
If they're right about some income but missed deductions or made errors, complete the response form explaining the corrections and include documentation.
You'll need proof: receipts, statements, Forms 1099 showing different amounts.
If you actually DID report this income or the IRS made a mistake, provide documentation showing you already included it on your return. Attach copies of your tax forms.
Common IRS errors: double-counting income, matching wrong taxpayer ID.
If you don't respond within 30 days, the IRS will send a Statutory Notice of Deficiency (90-day letter). That's when it becomes an actual tax bill and your options shrink significantly.