Formulary & Tiering Exceptions

What this guide covers

Formulary & Tiering Exceptions is for beginner advocates when the prescribed drug is not covered or is covered only on an expensive tier—and covered alternatives are not acceptable for this patient.

An exception asks the plan, usually through the PBM, to cover the drug anyway or lower the copay tier. It is not a generic complaint about drug prices; it is a structured request with prescriber clinical support.

Read Formularies & Drug Tiersfirst to confirm the drug's status. Pair denials with Denied Prescriptions.

This is educational information, not medical or legal advice.

Two types of exceptions

Formulary exception

Use when the drug is not on the formulary (or treated as non-covered). You ask the plan to add coverage for this patient because alternatives on the list are not medically appropriate. Pharmacy rejects often say drug not covered, non-formulary, or NDC not reimbursed.

Tiering exception

Use when the drug is on the formulary but on a high tier—for example Tier 4 or specialty coinsurance. You ask the plan to move it to a lower cost-sharing tier because equally effective lower-tier options failed or are not tolerable. Tiering exceptions change what the patient pays; they do not add a drug that is completely excluded unless the plan treats the request together.

Not the same as PA or step therapy

Prior authorization applies when the drug may be on formulary but needs plan approval before paying—see Rx Prior Authorization. Step therapy requires trying other drugs first—see Step Therapy (a step override is different from a formulary exception, but documentation often overlaps). Quantity limits cap how much can be dispensed per month—see Quantity Limits.

When to request an exception

Drug not on formulary

The prescriber believes formulary options are ineffective or would cause harm. Document trials, allergies, contraindications, or unique diagnosis needs.

Drug on formulary but unaffordable tier

The patient faces coinsurance on a high list price or specialty tier. Request a tiering exception if lower-tier drugs in the same class were tried or are ruled out clinically.

Try covered alternatives first

Plans expect a good-faith review of covered options. Advocates help by printing formulary alternatives before the appointment so the prescriber can document why each fails.

Build the request

Prescriber's role

The prescriber or office staff must submit clinical information. Patients can call and track status, but the medical statement comes from the clinic. Ask for a letter of medical necessity or the plan exception form, diagnosis and ICD-10 code, why each formulary alternative is inadequate, and medication history with dates and outcomes.

Evidence to attach

Include chart notes, discharge summaries, and specialist letters; pharmacy fill history for prior trials; lab results when criteria require them; and allergy or adverse event documentation. Organize like a mini appeal packet—see Building a strong appeal packet.

How to submit

Identify the PBM or plan from the Rx card—see PBMs & 2026 Reform. Download the plan's exception or coverage determination form from the provider portal. The prescriber submits with signature; keep fax confirmation or a portal ticket number. Request expedited review if delay risks serious harm.

Medicare, Medicaid & commercial

Medicare Part D

Part D uses coverage determinations. Exception requests are a type of determination. Plans generally must respond within 72 hours (standard) or 24 hours (expedited when health is at risk). Denial notices must explain appeal rights and deadlines.

Medicare formulary exception standards, simplified: covered alternatives would not be as effective for the patient and would likely cause adverse effects, or the requested drug is medically necessary for the patient. Exact wording is on CMS materials—the prescriber should mirror plan form language.

Appeals: Medicare Part D Drug Appeals, Medicare Part D.

Commercial & marketplace

Employer and marketplace plans use PBM exception forms. Timelines vary, often 48–72 hours. Fully insured plans may offer state external review after internal appeals—identify plan type on Plan type variations.

Medicaid

State preferred drug lists and managed care prior authorization may apply before exceptions. Some states use clinical criteria engines. Denials may go to plan grievance then fair hearing—see Medicaid guides on the Insurance topic.

After approval or denial

If approved, get effective dates and an authorization number. Have the pharmacy rebill. Confirm whether prior authorization or step therapy is still required separately.

If denied, read the reason—missing trials, wrong form, wrong exception type. The prescriber can add documentation and resubmit or appeal before the deadline on the notice.

Ask about temporary supply or transition fill rules while appealing, especially for Part D—the plan pharmacy line can explain.

Advocate checklist

Before you submit

Bring a formulary printout with the date, confirm the correct exception type (formulary vs tiering), list alternatives tried or contraindicated, and get the prescriber to commit to submit the same day if possible.

If denied

Calendar the appeal deadline from the notice. Fix gaps—labs, trial dates, diagnosis code. Request peer-to-peer if offered. Arrange a bridge supply through the prescriber while appealing. Use Medication Affordability if cash pay is temporary.

Scenarios beginners run into

Drug not on list at all

File a formulary exception with a trial table. Do not waste time on a PA-only workflow.

Only expensive brand works

If the brand is on formulary Tier 4, request a tiering exception. If the brand is off formulary, request a formulary exception. If a generic on Tier 1 works clinically, switch instead of filing an exception.

Drug removed in January

Request a formulary exception for continuity; attach proof of prior-year fills. Ask the plan about transition policy for Part D.

Steps done, still blocked

A step therapy override may be enough. If the drug is still non-formulary after steps, file a formulary exception with step documentation attached.

Tiering exception denied

The plan may say lower-tier drugs are available. The prescriber must explain why each is not equivalent—not just that the patient prefers a brand. Appeal with a specialist letter.

Exception approved, pharmacy rejects

Check for wrong strength, wrong pharmacy network, or prior authorization still required. Read the approval letter and call the PBM with the authorization number.

Related guides

Formularies & Drug Tiers, Rx Prior Authorization, Step Therapy, Quantity Limits, Denied Prescriptions, Specialty Pharmacy, and PBMs & 2026 Reform.

Official resources

CMS — Part D coverage determinations & appeals. Medicare.gov — Drug coverage (Part D rights). CMS — Part D formulary guidance.