IRS Notice Codes Explained: What Each Code Means

Published: June 18, 20245 min readIRS Notices

Receiving an IRS notice can be confusing and stressful. Each notice code tells you exactly what type of penalty or issue you're facing. Here's a comprehensive guide to the most common IRS penalty notice codes.

Failure to Pay Notice Codes

CP14 - Balance Due Notice

What it means: You owe taxes and haven't paid the full amount.

Penalty: Failure to pay penalty (0.5% per month)

Action required: Pay the balance or set up a payment plan within 30 days.

Relief options: First Time Abatement, Reasonable Cause, Payment Plan

CP161 - Second Balance Due Notice

What it means: You still owe taxes after the first notice (CP14).

Penalty: Continued failure to pay penalty

Action required: Pay immediately or contact IRS to avoid collection action.

Relief options: Payment Plan, Offer in Compromise, Currently Not Collectible

CP501 - Reminder Notice

What it means: You haven't responded to previous notices. Collection action may begin.

Penalty: Failure to pay penalty continues to accrue

Action required: Pay in full or contact IRS immediately

Relief options: Installment Agreement, Hardship Status

Failure to File Notice Codes

CP515 - Request for Tax Return

What it means: IRS hasn't received your tax return and believes you're required to file.

Penalty: Failure to file penalty may be assessed

Action required: File your return immediately or explain why you're not required to file.

Relief options: First Time Abatement, Reasonable Cause

CP516 - Income Tax Return Delinquency

What it means: Your tax return is significantly overdue.

Penalty: Failure to file penalty (5% per month, up to 25%)

Action required: File return immediately to stop penalty from increasing.

Relief options: File return + penalty abatement request

CP518 - Request for Tax Return (Final Notice)

What it means: Final notice before IRS prepares a return for you (Substitute for Return).

Penalty: Maximum failure to file penalty (25%)

Action required: File your return within 30 days or IRS will file for you.

Relief options: File original return to replace substitute return

Estimated Tax Notice Codes

CP2000 - Underreporter Inquiry

What it means: IRS computer matched your return with third-party reports and found discrepancies.

Penalty: Potential accuracy-related penalty (20%)

Action required: Respond within 30 days - agree, disagree, or provide explanation.

Relief options: Reasonable Cause, Accuracy-Related Penalty Relief

Collection Notice Codes

CP503 - Urgent - Balance Due

What it means: You haven't responded to previous notices. Collection action is imminent.

Penalty: All applicable penalties continue

Action required: Pay immediately or IRS may levy your assets.

Relief options: Payment plan, levy release, collection alternatives

CP504 - Intent to Levy

What it means: IRS intends to levy your state tax refund and other assets.

Penalty: All penalties continue + collection costs

Action required: Pay in full or contact IRS within 30 days.

Relief options: Collection Due Process hearing, installment agreement

Business and Employment Tax Codes

CP566 - Employment Tax Delinquency

What it means: You haven't filed required employment tax returns (941, 940, etc.).

Penalty: Failure to file and failure to deposit penalties

Action required: File all missing returns immediately.

Relief options: First Time Abatement, Reasonable Cause

Quick Action Guide by Notice Type

Immediate Actions by Notice Code:

High Priority (Act within 30 days):

  • • CP503, CP504 - Risk of levy
  • • CP518 - Substitute return threat
  • • CP2000 - Response deadline

Medium Priority (Act within 60 days):

  • • CP14, CP161 - Payment due
  • • CP515, CP516 - File return
  • • CP566 - Business filing

Don't Ignore IRS Notices

Each notice code represents a specific issue that requires prompt attention. Ignoring notices leads to escalating penalties and potential collection actions. Understanding your notice code is the first step toward resolving your tax issue.

Get help responding to your IRS notice with our penalty relief document preparation tools. We can help you understand your options and prepare the right response.