Skip to content 
Healthcare providers who want to participate in Medicare must complete the appropriate CMS provider enrollment requirements before they can maintain Medicare billing privileges.
For physicians, non-physician practitioners, group practices, clinics, institutional providers, and certain other healthcare organizations, enrollment can involve an NPI, PECOS application, professional and business information, ownership disclosures, supporting documentation, Medicare Administrative Contractor (MAC) review, screening, and periodic revalidation.
CMS currently directs providers and suppliers to obtain an NPI and complete Medicare enrollment through PECOS or, when appropriate, the applicable paper CMS-855 enrollment form.
Understanding these requirements before submitting an application can help healthcare practices avoid preventable enrollment problems and keep their Medicare records current.
The phrase CMS credentialing is commonly used to describe the process of establishing and maintaining a provider’s eligibility to participate in Medicare.
Technically, Medicare provider enrollment is often the more precise term for the CMS process. Commercial payer credentialing and hospital privileging are separate processes and may require additional documentation.
For Medicare enrollment, CMS may require information concerning the provider’s identity, professional qualifications, practice locations, organization, ownership and management, tax information, and other provider-specific requirements.
CMS’s current Medicare enrollment guidance identifies information that may be required, including legal identity information, organizational legal business name and TIN, professional licenses and certificates, ownership interests of 5% or more where applicable, managerial-control information, specialties, practice locations, accreditation information when applicable, and other enrollment data.
For most healthcare professionals and organizations, the first major step is obtaining the appropriate National Provider Identifier (NPI).
CMS directs providers who need an NPI to obtain one through the National Plan & Provider Enumeration System, or NPPES, before proceeding with Medicare enrollment.
Depending on the practice structure, this may involve:
Before Medicare enrollment, providers should review their NPPES information carefully.
Pay particular attention to the provider’s legal name, organization name, address, taxonomy, NPI type, and other identifying information.
Inconsistent information between NPPES, PECOS, tax records, professional licenses, and practice documents can complicate the enrollment process.
Healthcare professionals generally need to meet the applicable licensing and regulatory requirements for their provider type and the jurisdiction in which they practice.
Before submitting an enrollment application, verify applicable:
Institutional and specialized provider types can have additional federal, state, certification, survey, accreditation, or program requirements.
CMS notes, for example, that institutional enrollment may involve State Agency review and, in some cases, site visits before a final determination.
PECOS — the Provider Enrollment, Chain, and Ownership System — is CMS’s online Medicare enrollment management system.
PECOS can be used to:
CMS states that PECOS applications generally process more quickly than paper applications and are tailored so applicants provide information relevant to their enrollment.
Although PECOS is generally the preferred online method, understanding the CMS-855 application types is useful because different providers use different enrollment pathways.
Common Medicare enrollment forms include:
CMS-855I — Physicians and non-physician practitioners
CMS-855B — Clinics, group practices, and certain other suppliers
CMS-855A — Institutional providers
CMS-855O — Eligible physicians and non-physician practitioners enrolling solely to order or certify certain Medicare services
CMS confirms these application categories in its current enrollment guidance.
Selecting the appropriate enrollment pathway is important. The requirements for an individual physician may differ significantly from those for a medical group, laboratory, institutional provider, DMEPOS supplier, or another healthcare organization.
Practice-location information is an important part of Medicare enrollment.
Depending on the provider type and application, CMS may require information concerning the provider’s:
Providers should make sure the addresses reported to CMS accurately reflect their operations and are updated when changes occur.
CMS currently requires providers and suppliers to report certain changes—including changes in ownership, adverse legal actions, and practice location—within 30 days, while other changes generally must be reported within 90 days.
Ownership information is especially important for organizations.
Depending on the enrollment, providers may need to disclose individuals and organizations with applicable ownership or partnership interests, as well as individuals or entities exercising managerial control.
CMS’s Medicare enrollment guidance states that if a person or organization has a 5% or greater direct or indirect partnership or ownership interest, the applicable ownership information must be reported on enrollment records under the organization’s TIN. CMS also identifies W-2 employees and contracted individuals or organizations with managerial control among information that may be required.
Incomplete or inconsistent ownership information can complicate an enrollment application.
The documentation required for Medicare enrollment varies by provider and supplier type.
Depending on the application, supporting information can involve:
Do not assume that another provider’s Medicare enrollment checklist applies exactly to your practice.
A physician, behavioral health professional, group practice, laboratory, institutional provider, or DMEPOS supplier can have substantially different enrollment requirements.
CMS applies provider and supplier screening requirements as part of Medicare enrollment and program-integrity efforts.
The specific screening requirements depend on the provider or supplier category and applicable enrollment rules.
Certain providers may be subject to additional verification, site visits, or other screening activities.
Providers should therefore ensure that professional, business, ownership, practice-location, and enrollment information is complete and accurate before submission.
Submitting the application is not necessarily the final step.
Your Medicare Administrative Contractor (MAC) processes Medicare enrollment applications for its jurisdiction and may request additional information while reviewing an application.
CMS specifically instructs applicants to work with their MAC during enrollment and notes that the MAC may make additional requests for information.
Providers should monitor enrollment communications carefully and respond promptly when additional documentation or clarification is requested.
A delayed response can extend the enrollment process.
Some institutional providers and suppliers may be required to pay a Medicare enrollment application fee.
The fee does not apply universally to every healthcare professional or enrollment transaction.
CMS directs applicants to determine whether the application fee applies to their specific provider/supplier type and enrollment situation.
This is another reason provider-specific enrollment preparation is important.
A physician or other practitioner may be individually enrolled in Medicare but provide services through a group practice or another eligible organization.
In these situations, the provider’s Medicare benefits may need to be appropriately reassigned to the organization that will bill for the services.
Practices should make sure that the individual provider enrollment, organization enrollment, and reassignment relationships are properly established before relying on Medicare billing.
This becomes particularly important when:
Incorrect enrollment relationships can create downstream billing problems even when the individual provider is otherwise properly enrolled.
Some physicians and non-physician practitioners need Medicare enrollment because they order or certify services even if they do not intend to submit Medicare claims for their own professional services.
CMS currently states that an ordering and certifying provider must have an individual NPI, be enrolled in Medicare in an approved or opt-out status, and be an eligible specialty type.
Providers already appropriately enrolled as Medicare Part B providers generally do not need a separate enrollment solely for ordering and certifying.
CMS enrollment is not a one-time administrative task.
Practices should establish procedures for keeping Medicare enrollment information current when changes occur.
Examples can include:
CMS specifically warns that maintaining current enrollment information is important for avoiding problems with Medicare billing privileges.
Medicare providers and suppliers must periodically revalidate their enrollment information.
As of 2026, CMS states that most providers and suppliers generally revalidate every five years, while DMEPOS suppliers generally revalidate every three years. CMS can also request an off-cycle revalidation.
Providers can use PECOS to review their existing information, upload supporting documentation, electronically sign, and submit the revalidation.
CMS posts revalidation due dates in advance and also sends notices, but providers remain responsible for monitoring their own due dates.
Missing a revalidation deadline can create significant problems.
CMS states that failure to revalidate on time may result in a hold on Medicare reimbursement or deactivation of Medicare billing privileges.
If billing privileges are deactivated, the provider must submit a complete enrollment application to reactivate them, and Medicare does not reimburse services during the period of deactivation.
For this reason, practices should not wait until the last minute to review revalidation requirements.
Many Medicare enrollment issues are administrative rather than clinical.
Common problems can include:
A detailed enrollment review before submission can help identify many of these issues.
Healthcare practices sometimes assume that completing CAQH means the provider is enrolled with Medicare.
These are different processes.
CAQH is widely used by commercial health plans and other organizations to collect and maintain provider credentialing information.
PECOS is CMS’s Medicare enrollment management system.
A provider may therefore have a complete CAQH profile but still need to separately establish and maintain Medicare enrollment.
Keeping information consistent across NPPES, PECOS, CAQH, professional licenses, tax records, and payer applications can make credentialing administration more manageable.
Medicare and Medicaid should also not be treated as the same enrollment process.
Medicare enrollment is administered under CMS requirements and generally processed through PECOS and the appropriate MAC.
Medicaid enrollment is administered through individual state Medicaid programs, although federal requirements also apply.
A healthcare provider participating in both Medicare and Medicaid may therefore have separate enrollment obligations.
For example, a Texas provider may need to maintain Medicare enrollment while separately completing applicable Texas Medicaid enrollment through TMHP PEMS.
Provider enrollment and medical billing are closely connected.
A billing team can prepare an otherwise accurate claim, but reimbursement may still be disrupted when the provider’s enrollment information is incomplete, inactive, improperly linked, or inconsistent with the billing arrangement.
Credentialing and enrollment should therefore be treated as part of the broader revenue cycle management process.
Strong coordination between credentialing and billing teams can help practices identify enrollment issues before they become recurring claim problems.
Managing Medicare, Medicaid, and commercial payer enrollment can become time-consuming—especially for growing practices with multiple providers, locations, specialties, and payer relationships.
Nexa Digital Pro provides provider credentialing and enrollment support for healthcare professionals and organizations across the United States.
Our services can include:
Our goal is to help practices keep provider enrollment information organized, identify missing requirements early, and manage credentialing follow-up more efficiently.
Facing challenges with provider credentialing or payer enrollment? Nexa Digital Pro can help you navigate the process and keep your enrollment moving forward.
📞 210-940-9848
Nexa Digital Pro
Revenue. Operations. Digital Growth. One Partner.
CMS credentialing commonly refers to the enrollment and verification processes healthcare providers must complete to establish and maintain participation and billing privileges under Medicare. Medicare provider enrollment is generally the more precise term for the CMS process.
PECOS is CMS’s online Medicare enrollment management system. Providers can use it to enroll, update enrollment information, upload documents, report changes, and complete revalidation.
CMS lists obtaining an NPI as the first step for providers who do not already have one before completing the Medicare enrollment application.
Most Medicare providers and suppliers generally revalidate every five years. DMEPOS suppliers generally revalidate every three years, and CMS may require off-cycle revalidation.
No. CAQH credentialing and CMS Medicare enrollment are separate processes. Having an updated CAQH profile does not by itself establish Medicare enrollment.
Yes. Nexa Digital Pro can support Medicare enrollment, PECOS applications, revalidation, Medicaid enrollment, commercial payer enrollment, CAQH maintenance, credentialing follow-up, and related provider enrollment activities.
Author: Michael Clarke
