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IRS Notice CP30: Penalty for underpaying estimated tax

IRS Notice CP30 is a return adjustment letter from the IRS. The IRS charged a penalty because not enough tax was paid during the year through withholding or estimated payments. The IRS sends letters like this after it changes figures on a return.

What this letter usually means

The IRS charged a penalty because not enough tax was paid during the year through withholding or estimated payments. A change can raise or lower what you owe or your refund. The letter shows both the old and new figures.

Category: The IRS changed your return

What people usually do first

If you owe, pay by the due date on your notice.

What to have ready

What may come next

This letter does not point to a specific follow-up letter. Any later step will be described in mail from the IRS.

Read the IRS page

The IRS letter itself is the final word on what it means for you. Read the IRS page for CP30.

Common questions about CP30

What is IRS notice CP30?

The IRS charged a penalty because not enough tax was paid during the year through withholding or estimated payments.

How long do I have to respond to a CP30 notice?

The date to respond or pay by, if there is one, is printed on your letter. Check it, and read the IRS page for CP30 for more.

Is a CP30 notice a scam?

A real CP30 comes by mail and should match your own records. You can also sign in to your IRS Online Account on irs.gov to see your account directly.

What should I have ready for a CP30 notice?

The letter, every page, Your copy of the return, Records of your estimated payments, The dates you paid.

The OweRight app explains the CP30 letter type in plain English.

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OweRight is not the IRS and does not give tax or legal advice.

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