US Medical Billing
Prior authorization

Prior authorization under Medicaid

Prior authorization under Medicaid is an advance-approval requirement that a state Medicaid program — or a managed care plan under contract with the state — uses to confirm a service, drug, or item meets its coverage and medical-necessity criteria before the care is delivered. What sets it apart from commercial or Medicare rules is structure. Because Medicaid is a joint federal-state program, the services that require prior authorization, the forms, and the appeal procedures are set at the state level within federal limits, and differ further by delivery model — fee-for-service versus managed care. Any specific requirement should be verified against the current state or plan source, because these lists and rules change over time.

Updated 9 min read

Reviewed by Anwaar Tayyab

Director of Billing Operations ·

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Key takeaways

What sets Medicaid apart

Medicaid is not a single national plan. The federal government sets broad requirements and provides matching funds, while each state designs and administers its own program within those rules. The practical consequence for prior authorization is that there is no universal Medicaid authorization list. The procedures, drugs, and durable medical equipment that require review are defined state by state, and they are revised as budgets, policies, and clinical guidelines change. A requirement that applies in one state may not apply in another, and a requirement in place last year may have been added or removed since.

A second structural difference is that most states deliver Medicaid through more than one channel at once. Some enrollees receive care through traditional fee-for-service, where the state agency or its utilization-management contractor administers benefits directly. Many others are enrolled in managed care organizations that contract with the state and administer their own authorization rules within the state's requirements. Confirming which channel a member is in — through eligibility verification — is the first step, because it determines who sets the rule and where a request is sent. General guidance on verifying Medicaid eligibility describes how to identify the responsible plan before any care is scheduled.

Payer of last resort

Fee-for-service and managed care

The two delivery models share the same purpose but route the work differently. Under fee-for-service, requirements live in the state Medicaid provider manual and fee schedule, and requests go to the state agency or its designated vendor. Under managed care, each contracted plan publishes its own provider manual and portal, and the request goes to the specific plan in which the member is enrolled. The comparison below shows the dimensions that most often change between the two models; the details within each cell are set by the individual state or plan and should be confirmed against the current source.

How Medicaid delivery models handle authorization differently
How Medicaid delivery models handle authorization differently
DimensionMedicaid fee-for-serviceMedicaid managed care
Who sets the rulesThe state Medicaid agency or its utilization-management contractorThe contracted managed care plan, within state and federal requirements
Where requirements are publishedThe state provider manual, fee schedule, and bulletinsEach plan's provider manual and web portal
Who receives the requestThe state agency or its designated review vendorThe specific plan the member is enrolled in
First appeal pathA state fair hearing, which federal rules make available on request for a prior authorization decisionThe plan's internal appeal first, then a state fair hearing
Enrollment expectationProvider enrolled with the state Medicaid programProvider enrolled with the state and contracted with the plan

Directional only. Exact requirements, contacts, and timeframes are defined by each state and plan within the federal limits and change over time.

The federal rules beneath the variation

State flexibility sits on top of a federal floor. Several protections apply regardless of state design, and they shape how authorization must be handled. Federal regulation caps how long a standard or expedited authorization decision for items and services may take in both delivery models — one rule for contracted managed care plans and a parallel rule for state agencies operating fee-for-service — and requires notice of the decision along with appeal and fair-hearing rights when a request is denied. Drugs sit outside both of those timeframe rules — the fee-for-service rule excludes them, and the managed care rule routes covered outpatient drug decisions to a separate standard in the Social Security Act — so a drug request should not be tracked against the same clock. Coverage rules for children are broader than for adults: the Early and Periodic Screening, Diagnostic, and Treatment benefit obligates state programs to cover medically necessary services for enrolled children and adolescents under 21, which affects how necessity is evaluated. The federal interoperability and prior authorization rule adds standardized electronic processes and status transparency across Medicaid, the Children's Health Insurance Program, and other government programs over a phased timeline.

  • Decision timeframes: federal rules set outer limits for standard and expedited determinations on items and services in managed care and in fee-for-service alike, while drug authorizations follow a separate rule; the exact figures are defined in regulation and can be shortened by state law or contract — check the current source rather than assuming a number.
  • Coverage for children: the Early and Periodic Screening, Diagnostic, and Treatment benefit requires state programs to cover medically necessary care for enrollees under 21.
  • Notice and appeal rights: enrollees must receive written notice of an adverse decision and a defined path to challenge it, including a state fair hearing.
  • Standardized electronic processes: the CMS Interoperability and Prior Authorization rule phases in electronic submission and status reporting across Medicaid and related programs.
  • Drug review: state pharmacy programs and preferred drug lists commonly use step therapy, covered in more depth under prior authorization for medications.

How the process works in practice

Despite the variation, the operational sequence is consistent. The difference is where each step is verified. The steps below follow the same structure as the broader prior authorization workflow, adapted for Medicaid's dual delivery models.

  1. Confirm the delivery model and plan

    Verify whether the member is in fee-for-service or a specific managed care plan, since that determines who sets the requirement and where the request is submitted.
  2. Check the current authorization list

    Consult the state manual or the plan portal for the specific service, drug, or item. Lists are revised, so a prior result should not be assumed.
  3. Confirm provider enrollment

    Rendering and billing providers generally must be enrolled with the state Medicaid program even when serving managed care members. See Medicaid provider enrollment for how enrollment interacts with claims and authorization.
  4. Assemble medical-necessity documentation

    Gather the clinical records that support the request against the applicable criteria, including any child-specific standards where they apply.
  5. Submit and record the authorization number

    Send the request through the correct channel and capture the authorization number, approved units, and effective dates so billing can match them later.
  6. Track the decision against the timeframe

    Monitor the request against the applicable standard or expedited deadline, and escalate if the decision is not returned within the plan's or state's limit.

Retroactive eligibility

Denials, appeals, and fair-hearing rights

When a request is denied, Medicaid layers enrollee protections on top of the usual provider remedies. A managed care denial ordinarily goes first through the plan's internal appeal. If the internal appeal is unsuccessful, the enrollee generally retains the right to a state fair hearing. It is important to distinguish an authorization denial — a coverage decision that can be appealed — from a claim edit that can be corrected and resubmitted. Handling of authorization-related claim problems is covered under authorization-related denials, and the general escalation ladder appears in approvals, denials, and peer-to-peer review.

Internal (plan) appeal
In managed care, the plan-level review of an adverse authorization decision, which typically must be exhausted before a state hearing.
Medicaid fair hearing
A state administrative hearing that federal rules make available to enrollees to challenge a coverage decision, including a prior authorization decision; in managed care it follows the plan's internal appeal, and each state's procedures operate within the federal requirements.
Continuation of benefits
Under conditions set in federal regulation — 42 CFR 438.420(b) in managed care and 42 CFR 431.230(a) in fee-for-service — previously authorized services that are being reduced, suspended, or terminated may continue while an appeal or fair hearing is pending, provided the enrollee files in time.

An approval does not guarantee payment. The claim must still reflect an eligible member, the correct plan, coordination with any other coverage, matching authorized units, and submission within the applicable timely filing window. For comparison with the parallel government-sponsored model, see how these rules differ under Medicare Advantage.

Common questions

Does Medicaid require the same prior authorizations everywhere?

No. Because Medicaid is administered by each state within federal rules, the services that require authorization and the way requests are handled vary by state and, within a state, by the specific managed care plan. Any list should be confirmed against the current state or plan source because these change over time.

Who receives a Medicaid prior authorization request?

It depends on the delivery model. Under fee-for-service, the request goes to the state Medicaid agency or its utilization-management vendor. Under managed care, it goes to the specific plan in which the member is enrolled. Confirming the member's plan during eligibility verification determines the correct destination.

How does retroactive eligibility affect authorization?

Medicaid can grant coverage for a period before the month of application, so care is sometimes delivered before eligibility is confirmed. Whether and how authorization can be obtained after the service depends on the state and plan rules, which define any after-the-fact or urgent pathways.

Do children have different rules?

Often, yes. The federal Early and Periodic Screening, Diagnostic, and Treatment benefit requires state programs to cover medically necessary services for enrolled children and adolescents under 21, which can affect how medical necessity is evaluated for that population.

Does an approval guarantee the claim will be paid?

No. An authorization confirms that a service was reviewed against coverage criteria, but payment still depends on active eligibility, the correct plan, coordination of benefits, authorized units matching the billed service, and submission within the timely filing limit.

Authoritative sources

  • 42 CFR 438.210 — Coverage and authorization of services (opens in a new tab)

    eCFR. Governs Medicaid managed care. Paragraph (c) requires the plan to notify the requesting provider and give the enrollee written notice of any decision to deny a service authorization request, or to authorize a service in an amount, duration, or scope that is less than requested. Paragraph (d) sets the outer timeframes for standard and expedited authorization decisions and the conditions under which they may be extended, while paragraph (d)(3) routes covered outpatient drug decisions to a separate standard in the Social Security Act instead. Paragraph (f) requires the plan to publish annual prior authorization metrics, excluding drug data.

  • 42 CFR 440.230 — Sufficiency of amount, duration, and scope (opens in a new tab)

    eCFR. Sets the state plan baseline for the amount, duration, and scope of Medicaid benefits, which managed care coverage must at least match. Paragraph (d) lets the agency place appropriate limits on a service based on such criteria as medical necessity or on utilization control procedures — the authority behind state prior authorization requirements. Paragraph (e) is the fee-for-service prior authorization rule: it sets the outer timeframes within which the state Medicaid agency must decide standard and expedited requests for items and services, expressly excluding drugs, allows a shorter minimum timeframe established under state law, requires notice of the decision plus fair hearing rights, and requires the state to report prior authorization data publicly.

  • 42 CFR 431.80 — Prior authorization requirements (opens in a new tab)

    eCFR. The Medicaid fee-for-service half of the federal interoperability and prior authorization rule. Paragraph (a) requires a denial response to the provider to include a specific reason for the denial. Paragraph (b) requires the state to implement a standards-based prior authorization Application Programming Interface that is populated with the state's list of covered items and services requiring authorization, identifies the documentation the state requires, supports a HIPAA-compliant request and response, and communicates approval, denial, or a request for more information. Both requirements exclude drugs and carry staggered compliance dates, with extensions and exemptions available under paragraph (c).

  • 42 CFR 431.220 — When a hearing is required (opens in a new tab)

    eCFR. Requires the state agency to grant an opportunity for a hearing to any individual who requests it because of a listed determination, and lists a prior authorization decision among those determinations. It also extends the hearing right to any MCO, PIHP, or PAHP enrollee entitled to a hearing under part 438, subpart F.

  • 42 CFR 438.420 — Continuation of benefits while the MCO, PIHP, or PAHP appeal and the State fair hearing are pending (opens in a new tab)

    eCFR. Paragraph (b) lists the conditions under which a managed care plan must continue an enrollee's benefits: a timely appeal, an appeal involving the termination, suspension, or reduction of previously authorized services, services ordered by an authorized provider, an unexpired original authorization period, and a timely request for continuation. Paragraph (c) sets when continued benefits end.

  • 42 CFR 435.915 — Effective date (opens in a new tab)

    eCFR. Requires the state agency to make Medicaid eligibility effective for a period before the month of application where the individual received covered services during that period and would have been eligible at the time — the rule behind retroactive Medicaid coverage. Paragraph (c) requires the state plan to specify the date on which eligibility is made effective.

  • 42 U.S.C. 1396d(r) — Early and periodic screening, diagnostic, and treatment services (opens in a new tab)

    U.S. Code via govinfo. At subsection (a)(4)(B), covers early and periodic screening, diagnostic, and treatment services for individuals who are eligible under the plan and are under the age of 21; at paragraph (r)(5), defines those services to include such other necessary health care, diagnostic services, treatment, and other measures to correct or ameliorate defects and physical and mental illnesses and conditions discovered by the screening services, whether or not such services are covered under the state plan.

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