Reviewed July 2, 2026 · Health and dental plans for Canadians outside Quebec.
Two plans can both say "prescription drug coverage" and treat your exact medication completely differently. The reason is the formulary — the list of drugs a plan will actually pay for. It's the least glamorous part of any plan and one of the most important. Here's how to read it before you commit.
Is this you?
- You take a specific medication and want to know it'll be covered.
- You're comparing plans and they all claim to cover drugs.
- Your pharmacist once said your drug "isn't covered" and you didn't know why.
If any of those fit, this is for you.
What a formulary is
A formulary is the list of prescription drugs a plan agrees to pay for. Every drug plan uses one — provincial senior programs, catastrophic-cost programs, and private insurance all work from a formulary. Ontario's public formulary, for instance, lists thousands of covered medications, with additional drugs available only through a special-access process.
The rule is simple: on the list, the plan covers it under its rules; off the list, it generally won't pay unless the drug qualifies through an exception. That's why "does this plan cover drugs?" is the wrong question. The right one is "does this plan cover *my* drugs?"
Why a drug might not be listed
A medication left off a formulary isn't unsafe — it's just not on the plan's automatic-pay list. Common reasons:
- A lower-cost alternative is considered clinically equivalent.
- The drug is very new and hasn't been added yet.
- It's reserved for specific conditions through a special-authority process.
If your drug isn't listed, there's often still a path: an exception or prior-authorization request, or switching to a covered alternative your doctor agrees with.
Tiers: covered isn't a single thing
Many formularies sort covered drugs into tiers, and the tier decides how much cost or paperwork comes with the coverage. A typical structure:
- Generics — the easiest tier, lowest cost to you.
- Brand-name drugs with a generic equivalent — often covered only up to the generic's price.
- Specialized or high-cost drugs — covered, but usually only after prior authorization.
Knowing your drug's tier tells you not just *whether* it's covered, but *how easily*.
Generic substitution, briefly
Most plans pay based on the lowest-cost equivalent. If a generic exists and you choose the brand, many plans cover only the generic price and you pay the difference. Generics carry the same active ingredient and meet the same standards, so this usually saves money without changing your treatment. If you genuinely need the brand version, ask about the plan's exception process.
How to check a formulary before you choose
- List your prescriptions, noting any you need as brand-name.
- Check each drug against the plan's list — is it covered, and on which tier?
- Flag anything requiring prior authorization so you know the approval step exists.
- Ask about the exception process for anything not listed.
Ten minutes here prevents the worst plan-shopping surprise: discovering at the pharmacy that the coverage you paid for doesn't reach the drug you take.
The formulary is where "drug coverage" becomes real or doesn't. The fastest way to line up plans and see how each handles prescriptions in your province is to compare plans side by side. It takes about two minutes and needs no contact information to see prices.
Get Health Coverage is an independent comparison platform. We don't sell insurance and take no commission — plans are ranked by price. Availability and rates are set by each carrier and confirmed at application. Coverage is available in every province and territory except Quebec.
Frequently asked questions
What is a drug formulary?
A drug formulary is the list of prescription medications a plan agrees to pay for. Every drug plan — public provincial programs and private insurance alike — uses one. If a medication is on the formulary, the plan covers it according to its rules; if it is not, the plan generally will not pay unless the drug qualifies through a special-access or exception process. Formularies are updated regularly as new drugs are added and others change status.
Why would my prescription not be on the formulary?
Formularies don't include every drug on the market. A medication might be left off because a lower-cost alternative is considered equivalent, because it is very new, or because it is reserved for specific conditions through a special process. Being off the formulary doesn't mean the drug is unsafe — it means the plan won't automatically pay for it. If your drug isn't listed, ask about the plan's exception process and whether a covered alternative exists.
What are formulary tiers?
Many formularies sort covered drugs into tiers that affect what you pay or what approval is needed. A common pattern puts low-cost generics on the easiest tier, brand-name drugs with generic equivalents on a middle tier, and specialized or high-cost drugs on a tier that requires prior authorization. Checking which tier your medication sits on tells you not just whether it is covered, but how much friction and cost come with it.
What is generic substitution, and how does it affect coverage?
Generic substitution means a plan pays based on the lowest-cost equivalent version of a drug. If you or your doctor choose the brand-name version when a generic exists, many plans cover only up to the generic price and you pay the difference. Generics contain the same active ingredient and must meet the same standards, so substitution usually saves money without changing the treatment — but if you need the brand for a medical reason, ask about the plan's exception process.
How do I check a plan's formulary before I buy?
Make a list of your current prescriptions, including whether you need a brand-name version, then check each one against the plan's drug list and note the tier and any approval requirements. Provincial programs publish their formularies online, and private insurers can tell you how a specific drug is handled. Doing this before you choose a plan is the single best way to avoid an unpleasant surprise at the pharmacy counter.