How to request a formulary exception

What a formulary exception actually asks for

Every Part D plan publishes a formulary: the list of drugs it covers, sorted into cost tiers. A formulary exception is a formal request to your plan asking it to cover a drug that isn't on that list at all, as though it were. It's a narrower, more specific tool than prior authorization, which applies to a drug that already sits on the formulary but carries a review flag. With an exception, the starting point is that the drug simply isn't there.

A tier exception (sometimes called a tiering exception) is a different request with the same shape. The drug is covered, but it's priced on a higher cost-sharing tier than you think it should be, usually because a similar drug sits one or two tiers lower. Instead of asking the plan to add the drug to its list, you're asking it to bill the drug as if it were on a cheaper tier.

Formulary exception vs tier exception

The two get confused constantly, largely because the request looks identical from the outside: your prescriber writes a statement, the plan reviews it, and you get a coverage determination back. What differs is what's actually being asked for.

One rule applies to both: you cannot use a tier exception to move a specialty-tier drug down to a cheaper tier. Medicare excludes the specialty tier from tiering exceptions altogether, whatever the clinical argument.

How to request a formulary exception, step by step

The process is the same fixed sequence whether you're asking for a formulary exception or a tier exception. Only the content of the supporting statement changes.

1. Check the formulary first. Confirm whether the drug is missing entirely, which points to a formulary exception, or present but on an expensive tier, which points to a tier exception.
2. Ask your prescriber to write the supporting statement. This has to come from them, not you or the pharmacy, and it needs to state medical necessity and explain why formulary alternatives aren't appropriate for you.
3. Decide whether to request expedited review. If waiting could seriously jeopardise your health, say so; the deadline then drops from 72 hours to 24.
4. Submit the request to the plan directly, through its coverage determination line, fax, or online portal, not through the pharmacy counter.
5. Track the deadline from when the plan receives the supporting statement. That's the date the clock actually starts, not the date you first raised it.
6. Act on the decision. If approved, the pharmacy bills at the agreed tier from your next fill. If refused, read the denial notice and ask your prescriber about a redetermination.
7. Diarise the renewal. Ask your prescriber to resubmit before the plan year ends, since an approved exception doesn't automatically carry into the next one.

How fast the plan has to decide

An exception request is a type of coverage determination, so it runs on the same clock Medicare sets for any other Part D coverage decision. For a standard request, the plan must notify you no later than 72 hours after it receives your prescriber's supporting statement. For an expedited request, that shrinks to 24 hours. The distinction that trips people up is the start point: the clock begins when the statement lands with the plan, not when you first mentioned the problem to your doctor's office.

If your prescriber hasn't sent a supporting statement within 14 calendar days of an expedited request being opened, the plan can reset the clock and treat it as standard instead. That's another reason to chase the statement itself, rather than assuming the request is progressing once you've mentioned it to the surgery.

What the supporting statement actually has to say

This is where most requests succeed or fail, and it's rarely about the plan being obstructive. A vague statement gives a reviewer nothing to approve against. Medicare's rules set out fairly precisely what has to be in it, and the wording differs slightly by exception type.

For a formulary exception, the statement must say the requested drug is medically necessary because the formulary alternatives would be ineffective, would likely be ineffective, or would likely cause an adverse reaction or other harm. For a tier exception, it must say the lower-tier alternatives would not be as effective for you as the requested drug, would cause adverse effects, or both. In either case, medically necessary isn't a box to tick; the plan is entitled to ask why, clinically, this specific patient can't use what's already on the list.

A statement that simply says the patient prefers the requested drug, or that it's more convenient, gives the plan no clinical basis to approve. The strongest statements name the specific formulary alternative that was tried or considered, and say precisely what happened or why it was ruled out.

How long an approved exception lasts

Once granted, an exception stays valid for as long as three things remain true: your prescriber keeps prescribing the drug, it's still considered safe and appropriate for your condition, and your enrollment in the plan hasn't lapsed. In practice, that means it holds for the remainder of the current plan year.

It does not automatically extend into a new plan year. A plan is allowed to choose to continue an existing exception into the next year, but nothing obliges it to, and formularies are frequently rebuilt at renewal anyway. The safe assumption is that you'll need to go through the process again once your plan year turns over, ideally before your first refill of the new year rather than after a pharmacy rejection forces the issue.

A worked example

Here's an illustrative case, not a real patient, to show how the two exception types can apply to the same person at different points. Say a rheumatologist prescribes a newer biologic for a patient we'll call Grace, after two older drugs failed to control her joint pain. Her plan's formulary doesn't list that biologic at all, only a different one in the same class, so the pharmacy flags it as not covered. That's a formulary exception: the drug is absent, and the supporting statement needs to explain why the formulary's biologic isn't a safe substitute for Grace specifically, given what she's already tried.

Six months later, her plan adds the drug to its formulary, but on the highest branded tier, with a coinsurance far above what she was paying during the exception. The fix this time is a tier exception: the drug is now covered, so the argument shifts from it isn't listed to the lower-tier options don't work for me, and the statement has to be rewritten to match.

How often exception cases turn up in appeals

“Twenty-eight percent of cases were requests for Part D drugs not on the sponsor's formulary. The remaining 5 percent of IRE cases involved issues such as requests to pay a lower cost-sharing level and reimbursement for drugs provided outside of the sponsor's pharmacy network.”

That data is dated, but it's the most detailed public breakdown GAO ever published of what drives Part D appeals to independent review, and it's worth reading for the shape rather than the exact figures: formulary questions dwarfed tier and network issues combined. Nothing published more recently suggests that balance has shifted.

Common mistakes that sink an otherwise good request