Medicare credentialing services enroll your practice and each provider in Medicare so claims pay: the group through Form CMS-855B, each practitioner through Form CMS-855I (which now also handles reassigning their benefits to the group), and any provider who only orders or certifies through Form CMS-855O, usually filed online in PECOS. Then comes the part practices forget: reporting changes, revalidating every 5 years, and keeping effective dates aligned with when patients are actually seen.
Which Medicare enrollment form you need
| Who | Form | Purpose |
|---|---|---|
| Group practice or clinic | CMS-855B | Enrolls the organization that receives payment. |
| Individual physician or practitioner | CMS-855I | Enrolls the individual. The CMS-855I now captures reassignment of benefits to a group, which was previously collected on the CMS-855R; CMS has discontinued the CMS-855R. |
| Ordering or certifying only | CMS-855O | For eligible physicians and professionals who order or certify services but do not bill Medicare for their own services. |
| Opting out of Medicare | Opt-out affidavit | For practitioners who will contract privately with Medicare patients instead of billing Medicare. |
Most applications can be filed online through PECOS, Medicare's enrollment system, after the practitioner has an NPI from NPPES.
How long Medicare enrollment takes
CMS holds its contractors to processing standards in the Medicare Program Integrity Manual, chapter 10. For PECOS initial applications that need no site visit, development or fingerprinting, contractors must process 95 percent within 15 calendar days of receipt and all of them within 50; applications that need more information or a site visit take longer, and paper applications have longer standards still. Our guide to how long insurance credentialing takes has the full table.
Effective dates and billing before approval
- Effective date: for physicians and non-physician practitioners, the later of the date an application that was later approved was filed, or the date the provider first began furnishing services at a new practice location.
- Retrospective billing: up to 30 days before the effective date when circumstances precluded enrolling in advance, or up to 90 days when a Presidentially-declared disaster precluded it, provided all program requirements, including state licensure, were met.
The practical rule: file before the provider's first Medicare patient, not after.
Fees
The Medicare application fee in 42 CFR 424.514 applies to institutional providers submitting initial applications, new practice locations or revalidations. Practices should confirm in PECOS which fee, if any, applies to each application they file.
Free credentialing for 3 insurance payers for new billing clients.
Claim Your Free CredentialingKeeping Medicare enrollment active
- Revalidation every 5 years: providers must resubmit and recertify their enrollment information, and CMS contacts each provider when it is time.
- Report changes such as practice location, ownership and reassignment through PECOS within the required timeframes.
- Watch the mail and PECOS for revalidation and development requests; a missed request can deactivate billing privileges.
- Keep NPPES, PECOS and payer records consistent, so addresses and names match everywhere.
Opting out instead
A practitioner who does not want to bill Medicare can opt out by submitting an affidavit to each Medicare Administrative Contractor they would otherwise bill, with private contracts that meet Medicare's requirements. CMS's opt-out affidavit language states that opt-out lasts two years and renews automatically, and that cancelling the automatic extension requires written notice to the contractor at least 30 days before the next two-year period starts.
Common Medicare enrollment mistakes
- Seeing Medicare patients before filing, then discovering the retrospective window does not cover them.
- Enrolling the individual but not reassigning benefits to the group, so claims cannot pay the practice.
- Different practice addresses on NPPES, PECOS and claims.
- Missing a revalidation or development request.
- Filing for a provider who only orders services on the full billing application instead of the CMS-855O.
How Sterling Global Solution LLC handles Medicare credentialing
We file group, individual, reassignment and ordering enrollments in PECOS, answer contractor development requests quickly, confirm effective dates in writing, and calendar revalidation and change reporting for every provider. Because we also bill your claims, nothing is submitted for a provider before their Medicare effective date. New billing clients get free credentialing for 3 insurance payers; see our full credentialing services and how to get credentialed with every payer.
Frequently asked questions
Which form do I use to enroll in Medicare?
Is the CMS-855R still used for reassignment?
How long does Medicare credentialing take?
Can I bill Medicare for services before my enrollment is approved?
How often must Medicare enrollment be revalidated?
Sources
Centers for Medicare & Medicaid Services, Medicare Program Integrity Manual, chapter 10 (Rev. 13717): enrollment forms, CMS-855R discontinuation, processing standards and opt-out affidavit language.
Code of Federal Regulations, 42 CFR 424.520(d), 42 CFR 424.521(a), 42 CFR 424.515 and 42 CFR 424.514: effective dates, retrospective billing, revalidation and application fees.
Code of Federal Regulations, 42 CFR 405.410: conditions for opting out of Medicare.
Related reading
- How long does insurance credentialing take?. Medicare processing standards in full.
- How to get credentialed with insurance companies. Medicare, Medicaid and commercial, step by step.
- Credentialing services for therapists. Medicare for counselors and MFTs.
- Primary care billing services. Billing once your providers are enrolled.
Get your providers enrolled in Medicare
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