IRS CP504 Notice Explained: Final Warning Before Collection Action
What Is an IRS CP504 Notice?
The IRS CP504 notice is a notice regarding unpaid taxes and possible future collection activity. It is generally sent after earlier IRS notices remain unresolved.
Why Did I Get a CP504 Notice?
- You still have unpaid taxes
- Earlier IRS notices were not resolved
- Interest and penalties may have increased the balance
How Serious Is CP504?
CP504 is a serious notice because it means the IRS collection process is continuing. The notice warns about possible future collection actions if the balance remains unresolved.
Learn more here: What happens if you ignore CP504.
What Should You Do?
You may wish to review the notice carefully and compare it with your tax records.
You may also wish to contact the IRS or a qualified tax professional if you have questions about your situation.
See additional information here: How to respond to an IRS CP504 notice.
What Happens Next?
If the balance remains unresolved, the IRS may continue sending collection notices and warnings regarding possible future actions.
Can CP504 Be Wrong?
Sometimes payments are still processing or IRS records may not match your own records. Always compare the notice with your payment history and tax documents.
Will Penalties and Interest Continue?
Interest and penalties may continue increasing while the balance remains unresolved.
Can You Ignore a CP504 Notice?
Ignoring IRS notices can lead to additional notices and continued collection activity. Reviewing the notice promptly is generally recommended.
Bottom Line
An IRS CP504 notice means the IRS is continuing the collection process for unpaid taxes. Responding promptly may help you better understand the notice and available next steps.
Disclaimer: This article is for informational purposes only and does not constitute tax, legal, or financial advice.

Editor
25 years of experience managing tax, accounting, payroll, and employment-related information portals. Editor of Accounting Portal since 2011.
Read full bio →
Disclaimer
The information provided on Accounting Portal is for general informational and educational purposes only and does not constitute professional accounting, tax, financial, or legal advice.
While we strive for accuracy and timeliness, no representation or warranty is made regarding completeness or reliability. Always consult a qualified professional before making any business, tax, or financial decisions.
Neither Accounting Portal nor its authors are liable for any loss or damage resulting from the use of this information.
© 2026 Accounting Portal. All rights reserved.
