Understanding your CP518B business notice

What this notice is about

This is a final reminder notice that we still have no record that you filed your prior tax returns.


What you need to do

  • Send a signed paper tax return with all required schedules. 
  • Complete and return the Response form enclosed with your notice. Use it to explain one of the following:
    • The reason you’re filing late.
    • Explain why you believe you don’t need to file or that you already filed and more than four weeks have passed. 
    • That you filed with a different name or employer ID number (EIN) than the one shown on your notice.
  • If you filed within the last four weeks using the same name and EIN shown on your notice, you may disregard this notice.

How to send your information

  • Use the enclosed envelope to respond or fax your documents to 855-800-5944 using either a fax machine or online fax service. Protect yourself when sending digital data by understanding the fax service’s privacy and security policies.

If we don't hear from you

  • We may determine your tax for you. Penalty and interest can continue to accrue.
  • If you're owed a refund for the current tax year, or any prior year, it may be delayed because of this unfiled return.

You may want to


Frequently asked questions

Call us at the toll-free number shown on your notice. Have your paperwork ready when you call. 

You don't have to do anything if you filed your tax return within the last 8 weeks.

Sign, date and mail us a copy of the tax return with the completed Response form which was included with your notice. Make sure your name, social security number and tax year match on your return and notice.

You can request a payment plan.


Tips for next year

File your return on time. Consider filing your taxes electronically. Filing online can help you avoid mistakes and find credits and deductions that you may qualify for. In many cases you can file for free. Learn more about e-file.


Helpful information

Need help?