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Hiring a new physician can be exciting for a medical practice—but what happens when the physician is ready to start seeing patients before payer credentialing is complete?
This is one of the most common challenges in provider credentialing and medical billing. A physician may already have an active license, NPI, malpractice coverage, and employment agreement, yet still be waiting for Medicare, Medicaid, or commercial health plans to approve enrollment or add the physician to the practice’s contract.
The key point is simple:
A physician being licensed and clinically ready to practice does not automatically mean the practice can bill every payer for that physician’s services.
Practices need a payer-specific plan before scheduling patients. Depending on the payer, options may include waiting for credentialing, holding claims for an approved effective date, using an applicable retrospective billing provision, treating certain patients as self-pay when legally and contractually permitted, or using a legitimate substitute-physician arrangement.
Never simply bill the service under another credentialed physician who did not render the service.
“Credentialing” is often used broadly, but several different processes may be involved.
A new physician might be:
These situations are not interchangeable.
Before deciding whether the physician can see an insured patient, the practice should determine the physician’s exact status with that patient’s payer.
From a clinical perspective, a properly licensed physician may be able to provide care if all applicable employment, facility, malpractice, scope-of-practice, privileging, and state requirements have been satisfied.
The billing question is different.
Whether the practice can obtain reimbursement depends on factors such as:
Therefore, practices should not use a single policy for every payer.
The best solution to a credentialing delay is to avoid one whenever possible.
Begin provider credentialing and payer enrollment as early as practical after the physician accepts the position.
Prepare items such as:
Credentialing teams should also verify that names, addresses, taxonomy codes, practice locations, and other demographic information are consistent across applications.
A small discrepancy can create unnecessary follow-up.
Do not manage a new physician’s credentialing through scattered emails.
Create a centralized tracker showing each payer and the physician’s status.
At minimum, track:
| Payer | Application Status | Effective Date | Claims Strategy |
|---|---|---|---|
| Medicare | Pending/Approved | Confirm | Hold or bill according to Medicare rules |
| Medicaid | Pending/Approved | Confirm | Follow state Medicaid requirements |
| Commercial Payer A | Pending | Unknown | Verify payer policy |
| Commercial Payer B | Approved | Confirmed | Bill eligible dates |
| Medicaid MCO | Pending | Unknown | Verify MCO rules |
Also track:
This becomes the practice’s operational roadmap.
This is one of the most important rules.
A practice should not simply submit a claim under another physician’s NPI because that physician is already credentialed.
The billing provider, rendering provider, supervising provider, and other claim fields must accurately reflect the service and comply with the payer’s rules.
Using another physician’s credentials solely to bypass pending credentialing can create:
There are legitimate billing arrangements—such as certain Medicare substitute-physician arrangements—but they have specific requirements. They should not be confused with casually billing one physician’s work under another physician’s NPI.
Sometimes.
A common strategy is to allow the physician to provide services while the enrollment or credentialing application is pending and hold the claims until the payer confirms the physician’s effective date.
But this approach carries risk.
Approval does not necessarily mean that every service provided before the approval date becomes payable.
The payer may establish an effective date that is later than the physician’s first date of service.
Before holding claims, determine:
Never assume credentialing approval will automatically cover earlier dates of service.
Medicare has specific enrollment rules for physicians and certain non-physician practitioners.
CMS distinguishes between the effective date of Medicare billing privileges and a permitted retrospective billing period. Under applicable requirements, qualifying physicians and non-physician practitioners may generally bill retrospectively for services furnished up to 30 days before the effective date of billing privileges when the applicable conditions are met.
This can be useful when a physician begins providing services shortly before the Medicare enrollment process is completed, but it should not be interpreted as unlimited retroactive coverage.
For example, if a physician begins seeing Medicare patients substantially earlier than the permitted retrospective period, claims for the earlier dates may not be payable.
Practices should verify the physician’s actual Medicare enrollment and billing dates in PECOS/MAC records before releasing held claims.
Individual Medicare enrollment is not always enough.
If the physician works for a group practice and the group will receive Medicare payment for the physician’s services, the applicable reassignment of Medicare benefits must also be properly established.
CMS’s 2026 enrollment guidance confirms that reassignment has its own effective-date rules and that retrospective billing can apply in certain circumstances.
When onboarding a new physician, verify both:
Individual enrollment → Group reassignment
A physician can appear “Medicare enrolled” while the group relationship necessary for the intended billing arrangement is still incomplete.
Medicaid enrollment is not uniform nationwide.
Each state’s Medicaid program has its own enrollment procedures, effective-date policies, managed-care arrangements, and claims-filing requirements.
For example, Texas Medicaid states that claims may be submitted for dates of service on or after the provider’s effective enrollment date. Newly enrolled providers receive their effective date through their PEMS Welcome Letter.
Texas also provides specific circumstances in which enrollment dates may be retroactive, including rules involving certain Medicare-enrolled providers.
The same principle applies nationally:
Verify the individual state’s Medicaid enrollment and effective-date rules before seeing patients with the expectation of Medicaid reimbursement.
State Medicaid enrollment and participation with a Medicaid managed care organization may involve separate operational requirements.
In Texas, for example, TMHP specifically notes that Medicaid managed care organizations may have different administrative procedures for prior authorization, precertification, referrals, and claims or encounter filing.
Practices should therefore verify:
State Medicaid enrollment + MCO participation + effective date + authorization/referral requirements
before assuming a new physician’s services will be reimbursed.
Commercial payer credentialing can be particularly challenging because policies differ significantly among insurance companies and contracts.
One payer may permit a retroactive effective date.
Another may begin participation only on the credentialing committee approval date.
Another may establish a later contract effective date.
Some may allow claims to be held pending credentialing; others may not reimburse services rendered before the provider’s effective participation date.
Ask each payer:
Document the payer representative, call date, reference number, and response.
Possibly—but proceed carefully.
If a physician is not participating with a patient’s insurance, the practice should review the payer contract, applicable Medicare/Medicaid requirements, state law, patient-notice requirements, and other billing rules before treating an insured patient as self-pay.
Do not automatically tell a Medicaid or Medicare patient to pay cash simply because credentialing is pending.
Government-program rules can significantly restrict when a patient may be billed.
For Texas Medicaid, for example, TMHP provides specific requirements governing when Medicaid patients may be accepted as private-pay patients and emphasizes written notification in applicable circumstances.
A written financial policy does not override federal or state program rules.
A legitimate temporary physician arrangement may be an option in certain circumstances, but it is not a general workaround for credentialing.
Medicare has specific rules governing substitute-physician arrangements, including conditions surrounding the temporary substitution and claims reporting. CMS guidance describes use of the Q6 modifier for qualifying substitute physician services and generally applies a 60-day continuous-period limitation, subject to applicable exceptions.
Practices should not label a newly hired permanent physician a “locum” merely to bypass credentialing.
The arrangement must actually satisfy the payer’s requirements.
A major credentialing mistake is focusing entirely on approval and forgetting about claim deadlines.
If you plan to hold claims, maintain a report containing:
Review it weekly.
Texas Medicaid, for example, has special filing provisions for newly enrolled providers, but claims remain tied to the provider’s effective enrollment date and applicable filing limits.
Do not assume the payer will waive timely filing merely because credentialing took longer than expected.
Once approval arrives, do not immediately release every claim.
First confirm:
Credentialing approved → Effective date confirmed → Group affiliation confirmed → Network participation confirmed → Practice location loaded → Authorization valid → Claim date eligible
Then separate claims into:
Eligible for billing
Dates fall within the payer-approved effective period.
Needs payer review
Effective date or enrollment status is unclear.
Not billable to that payer
Date of service falls outside the approved period, and no applicable retrospective provision exists.
This prevents a large batch of avoidable denials.
The most frequent problems occur when practices rush onboarding without coordinating credentialing and billing.
Avoid:
A strong onboarding process connects credentialing, front desk, scheduling, billing, and revenue cycle management.
A practical workflow is:
Physician hired → NPI/NPPES reviewed → CAQH completed → Medicare/Medicaid enrollment submitted → Commercial payer applications submitted → Group affiliations/reassignments completed → Payer matrix created → Scheduling restrictions established → Pending claims tracked → Effective dates verified → Eligible claims released
This prevents the scheduling team from treating credentialing as something that only the billing department needs to know about.
Provider credentialing should begin before the first patient appointment, not after claims start denying.
Nexa Digital Pro provides credentialing, enrollment, and revenue cycle support for physicians, medical groups, clinics, and healthcare organizations across the United States.
Our services include:
If your new physician is ready to see patients but credentialing is still pending, our team can help review the enrollment status, organize payer follow-up, track effective dates, and coordinate credentialing with your billing workflow.
📞 210-940-9848
Nexa Digital Pro
Revenue. Operations. Digital Growth. One Partner.
A properly licensed physician may be clinically able to see patients, but whether the service can be billed to a particular insurance plan depends on that payer’s enrollment, credentialing, effective date, network, and billing rules.
Some practices hold claims when the payer allows retrospective billing, but approval does not guarantee that earlier dates of service will be covered. Confirm the effective date and timely-filing requirements before relying on this strategy.
Not simply because the rendering physician’s credentialing is pending. Claims must accurately identify providers according to applicable payer rules. Legitimate supervision, incident-to, or substitute-physician rules are separate arrangements with specific requirements.
Medicare allows qualifying physicians and certain non-physician practitioners limited retrospective billing under applicable conditions—generally up to 30 days before the effective date of billing privileges.
No. CAQH is a credentialing data repository used by many payers. Maintaining a complete CAQH profile does not mean every payer has credentialed, contracted, or activated the provider.
Start enrollment early, maintain a payer-specific credentialing tracker, establish scheduling rules, monitor held claims and timely-filing deadlines, verify effective dates, and coordinate closely between credentialing and billing teams.
Author: Michael Clarke
