guide

Express Scripts prior authorization: how the approval process works

Express Scripts prior authorization is a pharmacy coverage determination against the formulary: tiers, step therapy, exceptions, and why the appeal goes to the plan.
Jeffrey Morelli
Jeffrey Morelli
Published 22 July 2026

Express Scripts is a pharmacy benefit manager, not a health plan. That single fact reorganizes the entire workflow. Express Scripts does not decide whether a patient needs a knee replacement or an MRI; it decides whether a drug is covered under the pharmacy benefit of a plan that hired it, and on what terms. When a request stalls, the cause is usually that someone treated the PBM like a payer.

This guide is written for pharmacy technicians, billers, and prior authorization coordinators chasing drug approvals at volume. Every section leads with the operative fact.

What Express Scripts is

Express Scripts is a pharmacy benefit manager (PBM) operating under Evernorth, the health services division of Cigna. A PBM is a contractor: an employer, a union trust, a health plan, or a Medicare Part D sponsor hires it to build and police the drug benefit, which means assembling the formulary, contracting the pharmacy network, adjudicating claims at the point of sale, and running coverage determinations on the drugs that carry conditions.

The rules Express Scripts applies are the rules the plan bought. Two patients can present identical charts and identical prescriptions and get different answers, because their sponsors purchased different formularies. There is no single Express Scripts drug list to memorize, and a criteria document that governed one group last year may not govern the group in front of you today.

How to tell Express Scripts is in the picture. Read the pharmacy card, not the medical card. The drug benefit is carved out and sold separately from medical coverage on a large share of employer plans, so a member can carry a medical card from one carrier and a pharmacy benefit administered by an unrelated PBM. Inferring the PBM from the medical logo is the most common way a technician sends a request to a company that has no contractual relationship with the patient. The pharmacy card carries the routing data that matters: the BIN, the PCN, and the group identifier the claim adjudicates against. If the card is missing, a test claim at the dispensing pharmacy returns a rejection naming the real administrator.

Accredo. For specialty products, limited-distribution drugs, injectables, and therapies needing cold chain or clinical monitoring, the Express Scripts specialty pharmacy arm is Accredo. Approval and dispensing are separate steps: the coverage determination establishes that the plan will pay, and the specialty pharmacy fills and ships. Plans that route specialty through Accredo generally will not pay a retail claim for the same drug, so a prescription approved but sent to the wrong dispensing channel rejects at the counter and looks, to the patient, exactly like a denial.

What a pharmacy PA reviews

A pharmacy prior authorization is a coverage determination. The question is not “is this drug good medicine,” it is “does this prescription satisfy the conditions the plan attached to paying for it.” Those conditions live on the formulary, and four mechanisms account for nearly every request a coordinator will touch:

  • Tier placement. Cost-sharing tiers drive what the member pays. A punishing tier is frequently the real reason a prescriber wants intervention, and it is answered with a tiering exception rather than a medical necessity argument.
  • Step therapy. Fail-first: documented use of a preferred agent before the plan pays for the requested one. This generates the most avoidable denials, because the trial is usually real and the documentation of it is usually thin.
  • Quantity limits. A cap on units, days’ supply, or fills per interval. Exceeding it requires a clinical rationale for the dose or frequency, not a restatement of the diagnosis.
  • Non-formulary status. The drug is not on the list. This is not a finding that it lacks medical necessity; it is an absence, answered with a formulary exception.

Documenting step therapy is where requests are won. “Patient has tried and failed alternatives” is not a record. What clears the edit is each prior agent named, the dates taken, the dose reached, the duration at that dose, and the concrete outcome: inadequate response after an adequate trial, an intolerance with the reaction described, or a documented contraindication. Trials under a previous insurer, at another practice, or through samples still count, but only if the chart says so.

The medical benefit versus pharmacy benefit split. This is the distinction that most often sends a request into a void, and it turns on who buys the drug and how it is billed, not on how complex it is.

How the drug is obtained Which benefit pays Who authorizes
Dispensed by a pharmacy to the patient (retail, mail, or specialty), billed on an NDC pharmacy claim Pharmacy benefit The PBM administering that benefit, against the formulary
Bought by the practice, stocked, and administered in the office or infusion suite, then billed on a medical claim (buy-and-bill) Medical benefit The health plan or its medical utilization manager, not the PBM
Dispensed by a specialty pharmacy but administered by a clinician Depends on the plan’s policy for that drug Verify before submitting; the same molecule can sit on either side

Some drugs live on both sides depending on setting, and plans increasingly steer specific products from the medical side to the pharmacy side. When a buy-and-bill request is sent to the PBM, it does not get forwarded. It gets no answer, because the PBM has no claim to attach it to. Confirm which benefit the plan assigns the drug to before you build anything.

Working prior authorization across more than one payer? Start with Silna’s complete guide to prior authorization.

How to submit

Electronic prior authorization (ePA) is the default channel and the fastest one. Express Scripts accepts ePA through the standards-based ePA services that prescribers already use inside their EHR or through a browser, including CoverMyMeds, and it maintains its own provider portal for coverage determinations and status. Fax remains available and should be treated as a fallback: it strips out the structured question set, adds handling lag, and gives you no status visibility short of a phone call.

The advantage of ePA is not transmission speed. It is that the channel serves the plan’s actual criteria questions for that drug and that group, so the request is scoped correctly before it is sent. A fax is a guess about what the reviewer wants; an ePA question set is the reviewer telling you.

A complete pharmacy PA request contains:

  • Member identifiers exactly as printed on the pharmacy card, including the group identifier and, where asked, the BIN and PCN
  • Prescriber NPI, and a practice contact who can answer a callback the same day
  • Drug, strength, dosage form, directions, and quantity or days’ supply, matching the prescription
  • The ICD-10 diagnosis the drug is prescribed for, matching the chart
  • Tried-and-failed therapies with drug name, dates, dose, duration, and outcome for each
  • Dose rationale where the request exceeds a quantity limit or labeled dosing: weight, titration history, response at lower doses, or the guideline followed
  • Only the chart material the criteria call for: the labs, scores, or diagnostics named in the question set

Two habits shorten the cycle more than anything else. Answer the criteria question that was asked instead of attaching the whole chart; volume is not evidence, and a reviewer hunting for a lab value in forty pages will pend the request. And make the diagnosis on the request match the diagnosis in the note, because a mismatch reads as incomplete, and an incomplete request restarts the clock rather than pausing it.

Urgent requests. When waiting the standard window would seriously jeopardize the patient’s health or ability to regain maximum function, mark the request expedited and say so in clinical terms, not as an adjective. Expedited determinations carry a shorter mandatory decision window. Under Medicare Part D, a prescriber’s supporting statement that the standard timeframe would harm the patient obligates the plan to expedite.

How to appeal a denial

Start here: the appeal is not filed with Express Scripts. Express Scripts administers the determination on the plan’s behalf, but appeal rights run against the plan, and the plan owns the pathway. The denial notice names the entity that receives the appeal and the deadline that applies. Read it before you do anything else, because the routing on that notice overrides every general rule in this section.

Before appealing at all, sort the denial into one of three buckets. Two of them are not appeals.

  1. Administrative or technical. Wrong group, expired eligibility, a data mismatch, a request that belonged on the medical benefit, a missing field. Fix and resubmit. Filing an appeal here spends a level of appeal rights on a clerical problem and takes longer than a corrected submission. Our guides to reading denial codes and deciding when to appeal cover this triage in more depth.

  2. The drug is not covered, or is on the wrong tier. This calls for a formulary exception (or a tiering exception), not a medical necessity appeal.

  3. The drug is covered but the criteria were judged unmet. This is the medical necessity case, and it is the one the appeal process was built for.

Formulary exception versus medical necessity appeal. These get conflated constantly, which is why so many second submissions read like the first one. They are different arguments requiring different evidence.

Formulary exception Medical necessity appeal
The situation The drug is off the formulary, or the tier is the problem The drug is on the formulary; the plan says the PA criteria were not met
The argument Comparative: the covered alternatives are not appropriate for this patient Criteria-specific: the patient does meet the stated requirement, and here is the proof
The evidence Each formulary alternative addressed by name, with the reason it fails for this patient: prior failure, intolerance, contraindication, interaction The exact data point the criteria asked for: the trial record, the lab, the score, the diagnostic, the dose history
The common mistake Arguing the requested drug is excellent without addressing what is on the list Re-sending the same packet with a cover letter instead of the missing element

A prescriber’s supporting statement carries the weight in both, and generic language dilutes it. “Medically necessary” asserts a conclusion. “The patient took the preferred agent at the target dose for ten weeks with no reduction in symptoms, and the second alternative is contraindicated by the interaction described in the chart” establishes one.

Medicare Part D. Part D appeals are federally standardized, and the sequence does not vary by PBM:

  1. Coverage determination. The initial decision, including exception requests. This is the step Express Scripts typically administers for the sponsor.

  2. Redetermination. The first appeal level, filed with the Part D plan sponsor.

  3. Reconsideration by the Independent Review Entity (IRE), a contractor working for CMS rather than for the plan. This is the first genuinely independent look.

  4. Administrative Law Judge (ALJ) hearing at OMHA, subject to an amount-in-controversy threshold.

  5. Medicare Appeals Council review.

  6. Federal district court, subject to a higher amount-in-controversy threshold.

Part D deadlines are short and jurisdictional; miss one without good cause and the level closes. The prescriber can act as the member’s representative for Part D exception and appeal requests, which is usually faster than routing paperwork through the patient.

Commercial and employer plans. There is no single path. The plan’s appeal procedure governs, so the number of internal levels, the filing address, and the deadlines come from the plan documents and the denial notice. For fully insured plans, an external review by an independent organization is generally available once internal levels are exhausted, and its decision binds the plan. Self-funded ERISA plans follow their own claims procedure under federal rules; Medicaid managed care runs a plan appeal then a state fair hearing. In all of them, Express Scripts is the administrator, not the adjudicator of last resort.

What changed for 2026

Three shifts matter for teams working Express Scripts volume this year.

The federal ePA rule does not rescue pharmacy PA. The CMS Interoperability and Prior Authorization Final Rule (CMS-0057-F) is the change everyone in prior authorization is preparing for, and it is worth knowing what it does not reach: drugs are excluded from its Prior Authorization API requirements. CMS has an Electronic Prior Authorization initiative driving the medical side toward FHIR-based APIs and standardized denial reasons, but a team expecting that rule to modernize its drug workflow is waiting for something that was never in it. Pharmacy ePA runs on its own, older track, the NCPDP SCRIPT standard, which Part D plans have been required to support for several years. Do not let an EHR vendor conflate the two roadmaps.

Part D redesign keeps reshaping the exception conversation. The Inflation Reduction Act’s restructuring of the Part D benefit, including the annual out-of-pocket cap and the option for members to spread costs across the year, changed what the member experiences downstream of a determination. It did not change the criteria a coverage determination is judged against, and it did not change the appeal ladder. It does shift the calculus on tiering exceptions for some members, so verify the current year’s figures against CMS guidance rather than reusing last year’s handout.

PBM practices are under sustained scrutiny. Formulary construction, rebate economics, and steering to affiliated pharmacies have drawn attention from Congress, the FTC, and state legislatures. The practical consequence for a coordinator is not a new procedure. It is that formulary and channel policy is moving faster than usual, so a criteria document or dispensing rule you cached last year is a liability. Pull the current one for the specific group.

How Silna Reduces Denials

Pharmacy denials cluster into a small set of preventable failures, and none of them are clinical disagreements. The request goes to an administrator the patient does not have, because someone read the medical card. It targets the pharmacy benefit for a drug the plan pays under the medical benefit. It asserts a failed trial without the dates, doses, and outcomes that clear a step therapy edit. It argues medical necessity when the drug was never on the formulary. Every one of those is visible before the request leaves the practice.

Silna Health’s Care Readiness Platform automates that verification end to end: benefit checks and eligibility, identifying the administrator and the benefit lane for the specific drug and group, populating the request, checking it for the gaps that pend a determination, and submitting through the right channel. Silna’s Predictive Document Intelligence flags missing evidence and routing errors before submission, which is where a pharmacy PA is actually won or lost. By combining automation with built-in payor communication, Silna cuts pre-visit administrative work by 95%, per Silna Health, 2026.

Silna’s strongest adoption is among ABA therapy, physical therapy, and mental health practices, plus care management for older adults, where a single patient often carries a medical authorization and a drug coverage determination running on separate clocks against separate administrators. Silna coordinates both lanes so the first submission is the complete submission. See how it applies to your payer mix at silnahealth.com.

Key terms

Pharmacy benefit manager (PBM)
A contractor hired by a plan sponsor to administer the drug benefit: formulary, network, claims adjudication, and coverage determinations.
Coverage determination
The decision on whether the pharmacy benefit will pay for a drug and on what terms; the pharmacy equivalent of a prior authorization, and the step that precedes any appeal.
Formulary
The plan’s list of covered drugs with their tiers and utilization conditions. It belongs to the plan, so it varies by group, not by PBM.
Step therapy
A fail-first requirement: documented use of a preferred agent, with dates, dose, duration, and outcome, before the plan will pay for the requested drug.
Formulary exception
A request to cover a drug that is not on the list, or to move it to a lower tier. The argument is comparative: why the covered alternatives are inappropriate for this patient.
Accredo
The Express Scripts specialty pharmacy arm, used for specialty, injectable, and limited-distribution products on plans that route specialty dispensing there.
Independent Review Entity (IRE)
The CMS contractor that reviews a Part D case after the plan’s redetermination; the first level outside the plan’s control.

Frequently Asked Questions

How do I know if Express Scripts manages my patient’s drug benefit?

Look at the pharmacy card, not the medical card. The plan sponsor hires the PBM separately from the medical carrier, so a patient can hold a medical card from one company and have their drug benefit administered by an unrelated PBM. The pharmacy card carries the BIN, PCN, and group identifier the claim routes on. With no card in hand, a test claim at the dispensing pharmacy or an eligibility check on the pharmacy benefit will identify the administrator.

Does Express Scripts review medical procedures or imaging?

No. Express Scripts is a pharmacy benefit manager and reviews drug coverage under the pharmacy benefit only. Procedures, imaging, surgery, and other medical services are authorized by the health plan or the utilization manager the plan uses for medical review. This also applies to drugs the practice buys, stocks, and administers in the office and then bills on a medical claim: those go to the medical payer, not to the PBM.

Who do I appeal an Express Scripts denial to?

The plan, not the PBM. Express Scripts administers the coverage determination on the plan’s behalf, but appeal rights run against the plan that owns the benefit. For Medicare Part D that means a redetermination filed with the plan sponsor, then reconsideration by the Independent Review Entity, an ALJ hearing, the Medicare Appeals Council, and federal court. Commercial and employer plans follow the appeal procedure in their own plan documents. The denial notice names the correct recipient and deadline; follow it rather than a general rule.

What is the difference between a formulary exception and a medical necessity appeal?

The trigger and the argument. A formulary exception applies when the drug is not on the plan’s list, or is on a tier the prescriber wants changed; the argument is comparative, addressing each covered alternative by name and why it fails for this patient. A medical necessity appeal applies when the drug is covered but the plan judged the PA criteria unmet; the argument is criteria-specific, supplying the exact data the criteria asked for. Using an exception argument on a criteria denial, or the reverse, produces a second denial for the same reason as the first.

My step therapy request was denied even though the patient failed the preferred drug. Why?

Almost always because the failure was asserted rather than documented. A step therapy edit clears on a factual record: each prior agent by name, the dates taken, the dose reached, how long the patient stayed on it, and the specific outcome, whether that is inadequate response after an adequate trial, an intolerance with the reaction described, or a documented contraindication. Trials from a prior insurer, another practice, or samples count if the chart records them. Resubmit with the record rather than appealing the conclusion.

This article is general educational information, not medical or insurance advice. Formularies, coverage criteria, and appeal rights vary by plan, plan sponsor, and state, so consult a licensed healthcare professional or your plan administrator about your specific situation.

About the author

Jeffrey Morelli

Jeffrey Morelli is the Co-Founder and CEO of Silna Health, the first Care Readiness Platform built to remove the administrative barriers that delay care. Silna automates benefit checks, eligibility, and prior authorizations across 1,000+ payors, and is backed by $27M from Accel and Bain Capital Ventures. Before Silna, Jeff spent a decade in San Francisco building and scaling products for highly regulated industries, including leading go-to-market at Truework (Series C, acquired by Checkr).

Last reviewed: July 13, 2026.