The short answer: they are not the same. Credentialing is a payer's check of your qualifications. UnitedHealthcare, for example, verifies them at the primary source. Enrollment is a different process. In Medicare it establishes eligibility to bill Medicare. Contracting is often a third, separate step. And credentialing approval is not in-network status. Confirm your written effective date before you count on it.
What is credentialing?
Credentialing is how a payer checks your professional qualifications. Aetna lists training, licenses, certification or registration and academic background among the items it collects and verifies. Aetna also says credentialing is separate from network contracting.
UnitedHealthcare describes the order of review. Once it has a completed application, it performs primary source verification. It then presents your request to its credentialing committee.
What is payer enrollment?
In Medicare, enrollment is the process that establishes eligibility to bill Medicare. Approval means you have been found eligible under Medicare rules to receive a Medicare billing number and billing privileges. For Part B suppliers that number is the Provider Transaction Access Number (PTAN).
Physicians and other providers enroll or update their record through the Provider Enrollment, Chain and Ownership System (PECOS). The paper route is Form CMS-855. See our Medicare and PECOS enrollment page for how that process works. For enrollment across payers, see provider enrollment.
Is enrollment the same as being in-network?
No. With commercial payers, network status often depends on a contract as well.
Aetna says credentialing and contracting must both be complete before you become a network provider. You get a written notice when credentialing is done. UnitedHealthcare also says you must complete both credentialing and contracting before you begin seeing its members as an in-network provider. It says that receiving a contract to review does not confirm approval. Nor does it authorize you to see its members.
How long does each step take?
Timelines vary by payer. Aetna, for example, requires both credentialing and contracting before you become a network provider. So one step's timing does not tell you when you will be in-network.
Medicare: CMS processing standards
Per CMS, Medicare contractors work to these processing standards for initial and change-of-information Form CMS-855 applications:
Application type | 95% processed within | 100% processed within |
|---|---|---|
Paper: no site visit, development or fingerprinting | 30 calendar days of receipt | 65 calendar days of receipt |
Paper: requires a site visit, development or fingerprinting | 65 calendar days of receipt | 100 calendar days of receipt |
PECOS (online): no site visit, development or fingerprinting | 15 calendar days of receipt | 50 calendar days of receipt |
PECOS (online): requires a site visit, development or fingerprinting | 50 calendar days of receipt | 85 calendar days of receipt |
These are contractor standards, per CMS. They are not a promise for any single application.
Commercial payers: two examples
Each payer sets its own steps and timing. These examples show how different they are. They are not a forecast for your application.
Aetna publishes a staged schedule in its Spring 2025 provider bulletin. It lists these day ranges, in order: request for participation (listed as "Welcome to Aetna.com"), 1 to 30 days; contracting, 30 to 60 days; credentialing, 60 to 90 days; contracting again, 90 to 120 days. In that last stage, Aetna says that once you are approved in credentialing, it countersigns and returns your final contract. It says its systems then reflect your participation effective date. Aetna says to contact it if a request runs past these timelines. That is Aetna's published schedule, not a forecast for your application.
Delta Dental of Tennessee, a dental plan, says on its credentialing portal page that the approval process for an initial credentialing application can take up to 30 days after it receives the application. If you choose to see its members before approval, it says claims will be processed as non-participating. It also says it does not back-date the approval date. This is one plan's statement. It is not a forecast for your application.
How do you stay credentialed and enrolled?
Approval is not the end. Three things recur.
Medicare revalidation. CMS posts revalidation due dates seven months in advance. Your enrollment contractor sends a notice about three to four months before the due date. CMS says you are responsible for tracking that date yourself.
CAQH attestation. Providers must attest to their profile in the CAQH Provider Data Portal (formerly ProView) every 120 days. Illinois providers attest every 180 days. If a profile stays unattested past that window, its status changes to Expired. In most states, payers such as Aetna get your credentialing application from that profile. In June 2026, CAQH rebranded as DataSpring, powered by CAQH. Many providers still just call it CAQH. Our CAQH setup and maintenance page covers this.
Recredentialing. UnitedHealthcare says recredentialing is required at least every 3 years by the NCQA, CMS and many state regulatory organizations. If recredentialing is not completed, it says you may not be eligible to continue to participate in its network. Timing is set by each payer. One Delta Dental group (Delta Dental Insurance Company and its affiliates), for example, says its Provider Onboarding department starts re-credentialing approximately 120 to 180 days before the credential expiry date.
FAQ
Is credentialing the same as payer enrollment?
No. Credentialing checks your qualifications. Enrollment sets up eligibility to bill. In Medicare it establishes eligibility to bill Medicare. Commercial payers often add contracting as its own step. Aetna requires both credentialing and contracting before you join its network. UnitedHealthcare says you must complete both credentialing and contracting to see its members as an in-network provider.
Which comes first, credentialing or enrollment?
It depends on the payer. Aetna's join page lists contracting first. Then, if credentialing applies, Aetna gets your CAQH application to start credentialing. Your contract is finalized once credentialing is complete. Aetna's FAQ describes the contracting step after the written credentialing notice. Check each payer's own process before you plan.
Can I see plan members once I'm credentialed?
Credentialing approval alone does not make you in-network. A contract in hand is not proof of approval either. Wait for the written effective date from the payer. Under 42 CFR 424.520(d), in Medicare, the effective date for physicians and non-physician practitioners is the later of two dates. One is the filing date of an application that was later approved. The other is the date you first furnished services at a new practice location.
Not sure where your applications stand?
Request a credentialing audit. Pricing is by quote.