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CP521 notice: what it means and what to do
Got an IRS CP521 notice? Here is what it means, your deadline, what to check before you answer, and how to reply. Check your own letter free: it stays on your phone.
Check my CP521 notice freeWhat the IRS says this notice is about
If you received a CP521, CP521 (SP) or CP621 Notice, the IRS is reminding you that you have an installment payment due. Send your payment immediately.
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What you need to do
- Read your notice carefully. It's a reminder to send in your monthly payment.
- Pay by the due date. Go to the payments page to find out more about your payment options.
Your deadline
Answer by the date printed on your notice. If there is no date, answer as soon as you can, and call the number on the notice if you need more time.
What to check before you answer
Is this letter really from the IRS?
The IRS writes first by mail. A real letter shows a notice or letter number, your name and part of your tax ID number. The IRS does not ask for payment by gift card, crypto or wire transfer. If in doubt, sign in to your IRS online account, where many notices are listed.
Common questions
Your monthly installment agreement payment is due to us by a specific date.
Pay the amount due shown on the notice. Mail us your payment in the envelope we sent you. Include the bottom part of the notice to make sure we correctly credit your account.
If you don't send us a payment, the interest and penalties you'll have to pay will increase and you could default on your installment agreement.
If you have any questions, call us at the number at the top of the notice. A customer service representative will assist you.
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