Already Enrolled in Medicare? Reassign to a New Group
By George Ruan • October 7, 2026
Last reviewed: October 7, 2026.
If you are already enrolled in Medicare as an individual, joining a group usually takes a reassignment of benefits to that group, not a second individual enrollment. The group must be enrolled (or enrolling at the same time), and the reassignment needs dated signatures from both you and the group’s authorized official. Until the reassignment is approved, the group cannot bill Medicare for your services.
Sections
Do not file a duplicate individual enrollment
The most common misstep we see is starting a brand-new individual application for a clinician who is already enrolled in that state. PECOS reserves an initial individual enrollment for a first enrollment, a new state, or a new specialty. Contractors return duplicate filings as not needed for the transaction, and the real reassignment still has to be filed.
Before starting anything, check two records in PECOS: the clinician’s existing individual enrollment, and the reassignments already on file. The View/Manage Reassignments area shows active and pending receiving organizations, so you do not create a second request for a group that is already linked or pending.
Pick the path that matches the group
Joining an existing, Medicare-enrolled group: use the group’s reassignment path for the clinician. The CMS-855B instructions require the group to be enrolled, or concurrently enrolling, before reassignment takes effect.
Forming your own new PLLC, PC, or LLC as sole owner: PECOS has a built-in branch for this. When it says it found an existing enrollment and asks whether you are adding another entity you solely own, answer yes. That enrolls the new entity and bundles the reassignment.
Group not enrolled yet: the group’s organization enrollment comes first, or alongside the reassignment. A reassignment cannot attach to a group Medicare does not know about.
If you are not sure which situation applies, compare the CMS-855I and CMS-855B instructions or ask your Medicare Administrative Contractor (MAC) before filing.
Signatures are where reassignments stall
In our experience, more reassignments are held up by the signature page than by anything else. The reassignment authorization statement needs a signature and date from the clinician and from the group’s authorized official. Contractors have asked us for corrections when it was missing, unsigned, or undated.
Use PECOS electronic signatures where they are offered. If you sign on paper, the contractor may accept an upload, email, or fax, but one contractor told us mailed or stamped statements would not be accepted.
Make sure each person signs and dates the line that belongs to them: the clinician as the individual practitioner, and the owner or authorized official for the group.
When a contractor sends a correction request, plan on fresh dated signatures for the resubmission. Do not assume the original signed page can be reused.
Answer development requests by the date in the notice. Contractors give a response window and can reject the application if the complete correction does not arrive in time.
Other things that send applications back
Wrong contractor. An application sent to a MAC that does not cover the practice location comes back with instructions to send it to the correct contractor.
Name mismatches between the group’s IRS records, NPPES, and PECOS.
Assuming the application is approved because it was submitted. Wait for the contractor’s approval notice before releasing the group’s claims for that clinician.
If the person preparing the application needs PECOS access first, see our guide to authorizing your biller for Medicare enrollment. For a first-time group enrollment, start with how to credential Medicare as a therapist LLC. Bomi prepares reassignment packets and routes them for both signatures so the contractor gets a complete, dated statement.
Related Guides
Frequently Asked Questions
I already have a Medicare PTAN. Do I need a new one to join a group?
Not usually. In the same state and specialty, you keep your individual enrollment and add a reassignment to the group. A new state or specialty is different.
Who has to sign the Medicare reassignment?
Both the clinician and the group’s authorized official, each with a date. Missing or undated signatures are a frequent reason contractors ask for corrections.
Can the group bill Medicare while the reassignment is pending?
Hold those claims until the contractor approves the reassignment and confirms the effective date, then bill within the timely filing limit.
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Founded by George Ruan, Dax Earl, and Andrey Goder, Bomi helps independent therapists and group practices with insurance billing, credentialing, and payer follow-up. Bomi grew out of Dax’s experience helping his mother with her therapy practice, with a clear purpose: reduce the administrative burden of insurance while keeping practice owners in control.
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