Medicare PECOS Enrollment: Step-by-Step Guide

What Is Medicare PECOS?

PECOS (Provider Enrollment, Chain, and Ownership System) is CMS's online enrollment portal for Medicare providers. All physicians and non-physician practitioners must enroll through PECOS to receive Medicare billing privileges. Medicare enrollment services | free Medicare checklist.

CMS-855 Forms Explained

• CMS-855I — Individual practitioner enrollment (physicians, NPs, PAs, LCSWs, etc.)
• CMS-855B — Group practice/organization enrollment
• CMS-855R — Reassignment of Medicare billing rights (individual to group)
• CMS-855A — Home health agencies and hospice organizations

Step-by-Step PECOS Enrollment Process

1. Verify NPI registration matches current practice address
2. Complete CAQH ProView profile and attest
3. Submit CMS-855I through PECOS portal
4. Submit CMS-855B for group entity (if billing under group NPI)
5. Submit CMS-855R to reassign billing rights
6. Track application status in PECOS portal
7. Receive PTAN (Provider Transaction Access Number) upon approval
8. Configure PTAN in billing system before submitting claims

Choosing the Right CMS-855 Forms

Solo practitioner billing under your own NPI: CMS-855I only. Joining or forming a group: 855I (your individual enrollment) + 855B (the group's enrollment, if not already done) + 855R (reassigning your billing rights to the group) — the 855R is the most-missed form and the reason newly hired physicians can't bill despite being "enrolled." Home health and hospice agencies: 855A with Conditions of Participation requirements. All paths require CMS-588 EFT enrollment for electronic payments.

The Errors That Restart Your Clock

Top PECOS delays in order of frequency: NPPES address mismatch (your application address must match NPPES exactly — update NPPES first), wrong MAC (each state has an assigned Medicare Administrative Contractor; misdirected applications bounce), missing supporting documents (license, board certification, IRS CP-575 for groups), and unanswered development requests (MACs allow ~30 days; silence means rejection and full restart). PECOS portal status checks plus weekly MAC follow-up keep your file from sitting. Average timeline done right: 45–62 days to PTAN. Medicare enrollment service | 25-point Medicare checklist | step-by-step guide.