Is a CP2000 an audit?

No. A CP2000 is an automated computer matching notice — the IRS system compared what was reported to them against what you filed and found a mismatch. An actual audit is conducted by a human examiner and is much more invasive. The CP2000 is far more common and usually resolved with documentation.

What happens if I ignore a CP2000?

If you don't respond within 30 days, the IRS will assume the proposed assessment is correct and send a Notice of Deficiency (CP3219A). At that point you have 90 days to petition the Tax Court. After that, the tax is assessed and the collection process begins — starting with a CP501 balance-due notice, then escalating to liens and levies. The earlier you respond, the easier it is to fix.

Should I amend my return if I get a CP2000?

Not usually. The CP2000 process is separate from amended returns. If you agree with the IRS, you simply sign the response form and the IRS adjusts your account. Filing an amended return during a CP2000 case can actually cause processing confusion. Only amend if the IRS specifically instructs you to.

Notice CP2000 - Unreported Income

Type: Income Discrepancy | Level: critical

IRC Section: IRC § 6201

Response Deadline: 30 days

⚠ Deadline: You have 30 days from the date on the notice to respond before the proposed assessment becomes final. If you miss this window, the IRS can assess the tax and begin collection — even if the amount they calculated is wrong.

The IRS thinks you didn't report some income, and they're proposing a new balance. This is not an audit. Most of the time it's a simple paperwork mismatch — a 1099 you forgot about, a W-2 from a short-term job, or a brokerage statement that reported more than you realized. Don't panic. Don't ignore it. It can be fixed.

THE DECODER · “the mismatch letter”

A CP2000 is the notice everybody misreads. It is not a bill, and it is not an audit — it is the IRS saying the numbers third parties reported about you (employers, banks, brokers) don't match what your return reported, so here is a proposed change. Proposed. A response window is printed on the notice, and you can agree, partly agree, or disagree with documentation. What you do not do is ignore it — or pay it just because it looks official, because sometimes the IRS is missing context only you have. The move: respond, on time, in writing, with the record.

Chapter and verse: THE TAX CUTTERY® Guide to Federal Income Taxation, Chapter 17: The IRS as an Administrative Machine — §17.5, Responding to IRS Notices (p. 327–328). The exaTAX assistant quotes those pages on request — ask it about your CP2000.

The IRS receives copies of every W-2, 1099, and income statement filed under your Social Security number. When the numbers on your tax return don't match what was reported to them, their automated system flags the discrepancy and generates a CP2000. It lists each item of unreported income, the amount the IRS believes you should have reported, and a proposed new balance — including tax, penalties, and interest. This is the most common IRS notice, and it is not an audit. In most cases it's a paperwork mismatch that can be resolved with a written response and the right documentation.

Common Triggers

W-2 income not reported
1099-NEC or 1099-MISC income not reported
Brokerage or interest income not reported
1099-K payment processor income (gig workers and small business owners)
Dependent claimed by someone else with the same SSN

Resolution Steps

Step 1: Read every line item on the notice — the IRS lists exactly what was reported to them, by whom, and in what amount
Step 2: Pull your records for each item: W-2s, 1099s, brokerage statements, K-1s
Step 3: Compare what the IRS says to what you actually earned — mistakes on 1099s are surprisingly common
Step 4: If the IRS is right, agree in writing and pay the proposed amount or request an installment agreement
Step 5: If the IRS is wrong, respond in writing with documentation proving the correct amounts — do not amend your return unless instructed

Common Questions About CP2000

Is a CP2000 an audit?: No. A CP2000 is an automated computer matching notice — the IRS system compared what was reported to them against what you filed and found a mismatch. An actual audit is conducted by a human examiner and is much more invasive. The CP2000 is far more common and usually resolved with documentation.
What happens if I ignore a CP2000?: If you don't respond within 30 days, the IRS will assume the proposed assessment is correct and send a Notice of Deficiency (CP3219A). At that point you have 90 days to petition the Tax Court. After that, the tax is assessed and the collection process begins — starting with a CP501 balance-due notice, then escalating to liens and levies. The earlier you respond, the easier it is to fix.
Should I amend my return if I get a CP2000?: Not usually. The CP2000 process is separate from amended returns. If you agree with the IRS, you simply sign the response form and the IRS adjusts your account. Filing an amended return during a CP2000 case can actually cause processing confusion. Only amend if the IRS specifically instructs you to.

Notice CP2000 - Unreported Income

Common Triggers

Resolution Steps

Common Questions About CP2000

Related Notices

Additional Resources

This is an enforcement notice — the next move matters

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