IRS Notice CP521: Installment Payment Reminder
A reminder of your next monthly installment-agreement payment.
- Response deadline
- By the stated monthly due date
- Category
- Installment Agreement
- Severity
- Low
What does an IRS CP521 notice mean?
A CP521 is a routine monthly reminder that an installment-agreement payment is due. It states the payment amount, the due date, and the remaining balance. It confirms your payment plan is active and on track.
Why did you receive a CP521?
You have an active installment agreement with the IRS, and this notice reminds you that the next scheduled payment is coming due.
How to respond to a CP521 notice
Make the payment by the due date using your chosen method (direct debit, online payment, check, or payroll deduction). If you have direct debit set up, the payment will be drawn automatically and the notice is informational.
What happens if you ignore it?
Missing payments can put your installment agreement into default (see CP523), after which the IRS may terminate the agreement and resume collection, including levies.
Common resolutions
- Make the payment on time
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For informational purposes only. Not legal, tax, or medical advice.