CP2000 Notices

A CP2000 is not a bill and not an audit. It is a proposal: the IRS matched your return against W-2s, 1099s and other third-party forms, found a difference, and computed the tax it thinks you owe. What you do with the response deadline decides whether that proposal becomes an assessment.

The notice comes from the Automated Underreporter program, which is a computer match rather than a person reviewing your return. That matters. The IRS has not seen your records, and the proposed figure often ignores basis, deductions, or income that was reported somewhere the matching program did not look.

How the IRS arrived at the number

The notice lists each item the IRS believes was missing or misstated, the payer that reported it, and the tax, penalty and interest that follow. Common causes are a brokerage 1099-B reported at gross proceeds with no basis, a 1099-NEC for work that was reported under a different name or entity, a rolled-over retirement distribution treated as taxable, or a form issued to you in error.

An accuracy-related penalty of 20 percent is often included in the proposal. It is negotiable on the same response, and it frequently falls away once the underlying income question is resolved or reasonable cause is shown.

Your three options, and the deadline

• Agree: sign the response form and pay, or arrange payment. The proposal becomes an assessment.
• Partially agree: accept the items that are right, and explain, with documents, the ones that are not.
• Disagree: explain why the IRS is wrong and attach the proof, such as corrected forms, basis records, or a statement from the payer.

The response is due by the date printed on the notice, generally 30 days from its date. Ask for more time in writing before the date if you need it; the IRS will usually grant a short extension. Do not file an amended return to answer a CP2000. The response form is the channel, and an amended return can create a second, conflicting file.

What happens if you ignore it

Silence is treated as agreement. The IRS issues a statutory notice of deficiency, which starts a 90-day clock to petition the Tax Court before the tax is assessed. After that window the amount is assessed and collection begins. A CP2000 answered on time is usually resolved by correspondence; a CP2000 ignored is a much larger problem.

When a CP2000 points to something bigger

If the missing income is real and repeats across years, or if the return was prepared by someone else, the response has to be written with the next notice in mind. That is the point to get counsel: an answer that concedes the wrong facts can follow you into an examination or worse. See the notices and letters overview for how the sequence runs.