Medicare Provider Enrollment Through PECOS: 855I, 855B, 855R and Revalidation Explained

The forms, in plain language

• CMS-855I — enrollment for an individual physician or non-physician practitioner (NP, PA, CNS, psychologist, therapist and others).
• CMS-855B — enrollment for a group practice, clinic or other supplier that bills under its own tax ID (not for hospitals and institutional providers, which use the 855A).
• CMS-855R — reassignment of benefits: the individual authorizes Medicare to pay the group for services the individual renders. In PECOS this is a section within the 855I rather than a separate submission.
• CMS-855O — for physicians who only order, certify or refer and do not bill Medicare themselves.
• CMS-588 — Electronic Funds Transfer authorization, required for payment.
• CMS-460 — the participation agreement (“PAR”). Participating providers accept assignment on all Medicare claims and are paid the full fee schedule amount.

Enrolling a new group

The group needs a Type 2 NPI, a tax ID, a physical practice location (not a PO box), a bank account for EFT, and at least one authorized official who can sign. Submit the 855B through PECOS with the 588. Once the group is enrolled and has a PTAN, individual providers reassign to it. Groups are frequently rejected for a practice location that does not match the IRS documentation or the NPI record, so make all three agree before submitting.

Enrolling an individual and reassigning

Submit the 855I in PECOS with the reassignment section pointing to the group’s enrollment. The individual needs a Type 1 NPI, an active state license in the practice state, and for many specialties board or program documentation. If the individual will also bill under their own tax ID (a solo practice on the side), that is a separate enrollment.

Effective dates and retroactive billing

For physicians and non-physician practitioners, the effective date is the later of the date the application was received or the date the provider began furnishing services at the location, and the MAC may allow retrospective billing for up to thirty days before the effective date (ninety days when a presidentially declared disaster prevented enrollment). Submit as early as the provider’s start date allows; the window is measured from receipt.

Development requests

If something is missing or inconsistent, the MAC issues a development request with a deadline, typically thirty days. Respond through PECOS with exactly what was asked. Applications that are not corrected in time are rejected and must be submitted again from the beginning, with a new receipt date and therefore a later effective date.

Revalidation

Medicare requires providers and groups to revalidate enrollment every five years (every three for DMEPOS suppliers). The MAC sends notices to the correspondence address on file, and the due date is also published on the CMS revalidation lookup tool. Revalidating late leads to deactivation: claims stop paying, and reactivation does not restore the gap. Check the lookup tool for every provider and group at least twice a year, and keep the correspondence address current.

Keeping the record accurate

Changes of information (new location, new authorized official, bank change, a provider leaving the group) must be reported, most within thirty days for key changes and ninety for others. Terminate reassignments when a provider leaves; otherwise the group remains liable for claims billed under that provider’s NPI.

Frequent rejection reasons

• Practice location address differs between the NPI record, the IRS letter and the application.
• Authorized official not listed, or signature missing.
• EFT form attached without a voided check or bank letter.
• License in a different state from the practice location.
• Reassignment submitted before the group’s enrollment was approved.

Core MB handles Medicare enrollment, reassignment and revalidation tracking as part of credentialing, and the revalidation due dates sit in the portal next to every other expirable, so nothing lapses quietly.