The “P10” number that Medicare can ask from a health care provider over the phone is actually not “P10,” but PTAN. This is an acronym used by Medicare, which stands for “Provider Transaction Access Number.”

Get PTAN
To get a PTAN number, your health care office must be registered with Medicare. Medicare application forms are available on Medicare’s website.
Use PTAN
You’ll need your PTAN to get in touch with Medicare on a variety of topics. This is your authentication number for requests for customer service and Medicare’s interactive voice response system, where you can check the request status and eligibility of beneficiaries.
Protect a PTAN
Your PTAN number is your office’s identification and authentication number when dealing with Medicare. To secure your office’s financial dealings with Medicare and to protect patient privacy, remember to protect it well.