CP-575 Letter

Last updated February 11, 2026

What is a CP-575 Letter?

A CP-575 letter is an official document issued by the Internal Revenue Service (IRS) to confirm that a business has been assigned an Employer Identification Number (EIN). This letter serves as proof of your business’s EIN and legal name.

Why Do Insurance Payors Require a CP-575?

During the provider credentialing process, insurance companies verify that your EIN and business name exactly match the records held by the IRS. The CP-575 is the primary document used for this verification.If there are any discrepancies–such as a missing comma, different abbreviations, or an outdated business name–your application may be delayed or rejected. This can lead to delays in enrollment and payment processing.

How to Find Your CP-575 Letter

If your organization applied for an EIN, the IRS sent the CP-575 to the address on file at the time of registration. You may find a copy in your:

  • Business formation documents
  • Files from your accountant or attorney
  • Online records, if you received a digital version

What If You Lost Your CP-575?

The IRS does not reissue CP-575 letters. If you no longer have it, you must request a replacement document called a 147C Letter.

How to Request a 147C Letter from the IRS

To obtain a 147C Letter (which serves the same verification purpose as a CP-575), follow these steps:

  1. Call the IRS Business & Specialty Tax Line at 1-800-829-4933.
  2. Select the option for EIN inquiries.
  3. Verify your identity (you must be authorized to request EIN information).
  4. Request a 147C Letter to confirm your EIN.
  5. The IRS will mail or fax the letter (email is not an option).

Common Issues That Cause Delays

To prevent problems, make sure your CP-575:

  • Matches your W-9 exactly – Business name, spelling, and punctuation should be identical.
  • Reflects any name changes – If your business name has changed, update it with the IRS before submitting credentialing documents.
  • Aligns with your NPI and banking details – All credentialing paperwork should be consistent to prevent rejections.

Best Practices for Credentialing

  • Keep a copy of your CP-575 in your business records to prevent last-minute delays.
  • If you’re missing it, request a 147C Letter immediately to avoid enrollment slowdowns.
  • Verify all documents match before submitting credentialing applications to insurance payors.