IRS notices / CP521

IRS notice CP521: payment plan reminder

A CP521 reminds you that a monthly payment on your installment agreement is due and asks you to send it right away.

For individuals · Based on the IRS's own explanation of this notice

Deadline: Pay the amount shown by the due date on your notice.

What this notice means

You have an installment agreement with the IRS, and your next monthly payment is due by a specific date. This notice is your reminder.

While the plan is in place, the IRS still charges interest and any penalties that apply until the balance is paid in full. If you filed your return on time, the late payment penalty drops to 0.25% a month during the plan, instead of the usual 0.5%.

Why you got it

What to do now

  1. Read your notice. It's a reminder of the payment amount and due date.
  2. Pay by the due date. You can mail your payment in the envelope provided, along with the bottom part of the notice, or see the IRS payments page for other ways to pay.
  3. If you have questions, call the number at the top of your notice.

If you don't respond

If you don't pay, the interest and penalties you owe will grow, and you risk defaulting on your installment agreement. A default can lead to a CP523, which says the IRS intends to end the agreement.

See what a payment plan costs. Enter your balance and a monthly payment to get your payoff date and the total cost. Ask to have the penalties removed. See if you qualify for first-time abatement and get a ready-to-send letter.

Questions people ask

Do I still owe interest while I'm on a payment plan?

Yes. The IRS keeps charging interest and any penalties that apply until you pay the balance in full. If you filed on time, the late payment penalty is reduced while the plan is in effect.

What if I can't make this payment?

Contact the IRS right away. The IRS asks anyone who can't meet the terms of their payment plan to reach out immediately.

Related notices

This page explains the notice in plain English. Always follow the instructions and deadlines printed on your own notice. IRS: Understanding your CP521 notice · IRS Publication 594, The IRS Collection Process (PDF)

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