TL;DR — The CMS-855R reassigns an individual provider’s Medicare payment rights to a group practice so the group can bill for that provider’s services. Both sides must already be enrolled — the provider via CMS-855I, the group via CMS-855B. Without an 855R on file for each provider, the group cannot bill Medicare for their services. Typical processing: 30–45 days. Reassignment of Medicare benefits is the mechanism that lets a group practice or organization bill Medicare for services performed by an individually enrolled provider. The CMS-855R is the form that creates that link.

Here’s the basic structure: The individual provider is enrolled and has their own Medicare billing privileges (via CMS-855I). The group practice is enrolled and has its own billing privileges (via CMS-855B). The CMS-855R is the bridge — it reassigns the provider’s payment rights to the group so the group can bill on the provider’s behalf.

Without a CMS-855R on file for each provider, the group cannot bill Medicare for that provider’s services, even if both the provider and the group are individually enrolled.

What reassignment actually means

Reassignment transfers the right to receive Medicare payment for services from the individual provider to the organization. In practical terms:

The group submits claims under the group’s NPI with the individual provider listed as the rendering provider
Medicare pays the group directly
The group pays the provider per their employment or contractor agreement
The provider cannot simultaneously bill the same service under their own individual NPI

Reassignment does not eliminate the individual’s enrollment — it supplements it. The provider still needs an active CMS-855I enrollment to have billing privileges that can be reassigned.

Who files the CMS-855R

The CMS-855R is filed by the individual provider who is reassigning, on behalf of the relationship between that provider and the receiving organization. In PECOS, it’s managed through the individual provider’s enrollment record.

You need a CMS-855R if:

You’re employed by or contracting with a group practice that bills Medicare for your services
You’re an individual provider joining an organization that will bill under its group NPI
You’re a physician employed by a hospital and the hospital bills “provider-based” services

You do not need a CMS-855R if:

You only bill under your own individual NPI (you’re in independent solo practice)
You’re an institutional provider (hospital, SNF) — institutional billing works differently

Step-by-step: Filing the CMS-855R

Via PECOS (recommended)

Step 1: Access your individual enrollment in PECOS Log in with your individual I&A credentials. Navigate to your individual enrollment record (the one associated with your CMS-855I).

Step 2: Initiate a reassignment transaction Within your enrollment, add a reassignment. You’ll need:

The NPI of the receiving organization (your employer/group)
The name and PTAN of the receiving organization
The effective date you want reassignment to begin

Step 3: Specify the relationship Indicate whether this is an employment relationship, independent contractor relationship, or other arrangement.

Step 4: Sign the application Both you (the provider) and an authorized official of the receiving organization must sign the CMS-855R. In PECOS, this requires both parties to have PECOS access.

Step 5: Submit and track Once submitted, you can track status in PECOS. Processing typically takes 30–60 days.

Via paper

Use the current CMS-855R paper form from cms.gov. Complete:

Section 1: Reassigning provider information (your information)
Section 2: Receiving organization information (employer/group)
Section 3: Relationship type
Signature block: Both signatures required

Mail to your MAC (your MAC, not NSC — DMEPOS reassignments follow slightly different rules).

⚠️ Risk flags

⚠️ Reassignment terminates automatically when the relationship ends. When a provider leaves a group, the group must file a CMS-855R termination (or the provider must, depending on circumstances). If the group continues billing for a provider’s services after the provider leaves and the reassignment isn’t terminated, those claims are fraudulent. This is a compliance landmine for groups with high provider turnover.

⚠️ Can’t reassign to an unenrolled organization. The receiving organization must be enrolled in Medicare (approved CMS-855B on file) before a reassignment can be established. You can’t reassign to an organization that’s simultaneously applying for enrollment — the organization’s approval must come first (or in practice, a simultaneous submission can work, but there will be a gap).

⚠️ Revalidation affects reassignments. If a provider’s individual enrollment is deactivated due to missed revalidation, all reassignments from that provider are also suspended. Groups with deactivated providers need to address the individual’s reactivation first.

⚠️ Multiple simultaneous reassignments are permitted. A provider can have active reassignments to multiple organizations simultaneously (common in locum tenens or multi-group arrangements). Each requires its own CMS-855R.

Common errors

Error: Receiving organization can’t be found in PECOS Cause: Organization isn’t enrolled in Medicare yet, or there’s a Type 2 NPI mismatch. Fix: Confirm the organization’s enrollment status and NPI before initiating reassignment.

Error: Application returned — missing authorized official signature Cause: Only the individual provider signed; the receiving organization’s authorized official signature is missing. Fix: In PECOS, the organization’s designated authorized official must also complete their portion of the transaction.

Error: Claims denied post-reassignment Cause: Reassignment effective date doesn’t cover the service date, or the provider’s individual enrollment became inactive. Fix: Check the reassignment effective date in PECOS. Verify the individual provider’s enrollment is still active.

Processing timeline

Filing method	Typical processing time
PECOS	30–60 days
Paper	60–90 days

Reassignment approvals are generally faster than initial enrollment applications because the MAC is linking two already-verified records.

Terminating a reassignment

When a provider leaves a group:

The provider should file a CMS-855R termination in PECOS (or paper)
The termination becomes effective on the date specified (not retroactively)
After termination, the group can no longer bill for the provider’s services
The provider’s individual enrollment remains intact — they can reassign to a new organization or begin billing independently

⚠️ File the termination promptly. Claims submitted after a relationship ends but before a termination is filed are a compliance risk for the group.

Questions about how reassignment works in your specific situation? Ask Mae → Free enrollment audit from Metolius Health →