IRS Forms

What is a “CP575”? When you obtain an EIN from the IRS, you receive a Form SS-4 (Notice CP-575) either by .pdf download or in the mail (your choice). The form is most often referred to simply as a “CP575”. It is important that you retain this document for the life of your entity as it cannot be recreated by the IRS. You will need this document to enroll with Medicare, Medicaid, and some commercial carriers to provide proof of the legal name and EIN. If you do not have the original CP575, then you can request a replacement letter 147C to verify your EIN. These two documents are the only documents that are acceptable proof of your legal business name and EIN as is on file with the IRS.

Click here for an example of a CP575. If you do not have your original CP575 or you have changed your business name with the IRS then you will need to request a replacement letter 147C by calling the IRS business center at (800) 829-4933. The hours of operation are 7:00 a.m. – 7:00 p.m. local time, Monday through Friday.  Allow 4-6 weeks for processing the request.

W-9, Taxpayer Identification Verification Form

Medicare Provider Enrollment Forms and Information

Listing of Medicare Intermediaries by State

Medicare Provider Enrollment Regulations

Taxonomy Codes
Explanation of taxonomy codes with link to a code crosswalk published by Medicare
Link to Washington Publishing for an interactive search of taxonomy codes

Medicare Enrollment Forms
CMS 855A Medicare Enrollment Application – Institutional Providers
CMS 855B Medicare Enrollment Application – Clinics/Group Practices and Certain Other Suppliers
CMS 855I  Medicare Enrollment Application – Physicians and Non-Physician Practitioners
CMS 855O Medicare Enrollment Application – For Eligible Ordering and Referring Physicians and Non-Physicians
CMS 855R Medicare Enrollment Application – Reassignment of Medicare Benefits
CMS 855SMedicare Enrollment Application – Durable Medical Equipment, Prosthetics, Orthotics, and Supplies (DMEPOS)
CMS 588 Electronic Funds Transfer (EFT) Authorization Agreement
CMS 460 Medicare participating physician or supplier agreement