IRS CP166 Notice: A Monthly Payment Did Not Go Through
Notice Instructions: Follow the payment instructions and due date on your notice.
A missed withdrawal is a reason to check the payment and the account—not guess what happened.
CP166 says the IRS could not withdraw your monthly installment payment because the bank account had insufficient funds.
Read The IRS Guidance For CP166 · Source checked October 11, 2026.
What to Check Next
- Step 1: If the missed payment is still unpaid, make the payment using the IRS instructions.
- Step 2: Check that the bank account has enough money for the next scheduled withdrawal.
- Step 3: If the account details or withdrawal seem wrong, check with your bank and review the agreement through the IRS Online Payment Agreement tool.
Common Questions About CP166
- Is CP166 About Health Insurance?
- CP166 concerns a failed monthly installment payment, rather than a health-coverage requirement.
- Does Mailing A Payment Stop The Automatic Withdrawal?
- The IRS says a mailed payment does not stop the scheduled withdrawal under a Direct Debit Installment Agreement.
Understand the Notice.
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