GLP-1 Covered but Still Expensive? Deductible and Copay Math

A GLP-1 can be "covered" and still cost hundreds of dollars a month, because coverage only means your plan shares the cost. What you actually pay depends on three things: whether the drug is subject to your deductible, whether you owe a flat copay or a percentage coinsurance, and when in the year you hit your out-of-pocket maximum. Below is the plain-English version, then a worked 12-month example so you can see the numbers move.

What do formulary, deductible, copay and coinsurance mean?

Term	What it means	What it does to your GLP-1 bill
Formulary	The plan's list of covered drugs, usually sorted into tiers	Being listed is step one, not the price
Tier	The cost-sharing level a drug sits in	Higher tiers usually mean higher copays or coinsurance
Prior authorization	Plan approval needed before it pays	No approval, no coverage, no matter the tier
Deductible	What you pay before the plan starts sharing costs	If it applies to drugs, you may pay the full negotiated price until it's met
Copay	A flat dollar amount per fill	Predictable: $X every month
Coinsurance	A percentage of the plan's negotiated price	Unpredictable unless you know that price
Out-of-pocket maximum	The most you pay for covered in-network care in a year	Once you hit it, covered costs drop to $0 for the rest of the plan year

For context, KFF's 2026 employer survey found that among workers in plans with three or more drug tiers, the average fourth-tier copay was $136 and the average fourth-tier coinsurance was 30% (35% for third-tier drugs). For workers with a general annual deductible on single coverage, the average deductible was $1,955.

Why the same GLP-1 costs $25 in one plan and $1,000 in another

Meet Sam. Sam's prescriber has a prior authorization approved, and the drug is on the formulary. Good news! Then the first pharmacy receipt arrives.

Whether Sam pays $25 or $1,000 that day depends on plan design, not on the drug. Let's run three versions of Sam's plan for a full year.

Assumptions (hypothetical, for illustration only): the plan's negotiated price is $1,000 per monthly fill, Sam fills 12 times, and Sam has no other medical costs this year. Real negotiated prices vary and are rarely shown to members.

Plan A: flat copay, deductible doesn't apply to drugs

• Tier 4, $136 copay per fill
• Yearly total: 12 × $136 = $1,632

Boring, predictable, and easy to budget.

Plan B: deductible applies to drugs, then 30% coinsurance

• Deductible: $1,955, then 30%

Month	What happens	Sam pays
Jan	Full price, all toward deductible	$1,000
Feb	$955 finishes the deductible; 30% of the remaining $45	$968.50
Mar–Dec	30% of $1,000 × 10 fills	$3,000
Year		$4,968.50

Same "covered" drug, three times Plan A's cost, and a brutal first two months.

Plan C: high deductible, then 20% coinsurance, with an out-of-pocket max

• Deductible $3,000, then 20%, out-of-pocket maximum $5,000

Month	What happens	Sam pays
Jan–Mar	Full price until the deductible is met	$3,000
Apr–Dec	20% of $1,000 × 9 fills = $1,800	$1,800
Year	Under the $5,000 max, so it never kicks in	$4,800

If Sam also had a surgery that year, the out-of-pocket max could arrive sooner and later fills would cost $0. That's why the yearly view matters.

How savings cards and "copay accumulators" change the math

Manufacturer savings cards can help, but read the caps:

• Lilly's card for commercially insured people whose plan covers the Zepbound single-dose pen says you may pay "as little as $25." But savings are capped at $100 per month and $1,300 per calendar year.
• Novo Nordisk's Wegovy offer for commercially insured people is likewise "as little as $25," with a $100 per month maximum.

So in Plan B, a $300 coinsurance bill becomes roughly $200 with a $100-capped card, not $25. In Plan A, a $136 copay could get much closer to $25.

There's another wrinkle. Some plans don't count what the card pays toward your deductible or out-of-pocket maximum. These are often called copay accumulator or alternate funding programs. Lilly's own terms say it can reduce or end savings if a plan doesn't apply card payments to your cost-sharing. Ask your plan directly: "Do manufacturer card payments count toward my deductible?"

Government-insured people (Medicare, Medicaid, TRICARE and others) generally can't use these cards. Our savings offer checklist covers the fine print.

When does self-pay beat "covered"?

Sometimes. In Plan B, Sam pays $300 a month after the deductible. The manufacturer's self-pay price for many Wegovy pen doses was $349 in October 2026, and the Zepbound KwikPen ran $299–$449 depending on dose (with the higher-dose price requiring a refill within 45 days). For a few months the gap can be small. But self-pay money generally doesn't count toward your deductible or out-of-pocket max, so it doesn't help if you expect other big medical bills. Run both columns before you decide.

Your fill-in calculator

Line	Your plan
Negotiated price per fill (ask the plan for an estimate)	$
Does the deductible apply to this drug? (Y/N)
Deductible remaining	$
Copay ($) or coinsurance (%) after deductible
Out-of-pocket maximum remaining	$
Savings card monthly cap / yearly cap	$ / $
Does card money count toward deductible? (Y/N)
Estimated cost per fill, Jan → Dec

Ask the plan to estimate your cost "at my current point in the year." Member portals often have a drug-price tool that uses your actual deductible status.

Questions to ask your plan today

1. "What tier is my drug, and is it covered for my diagnosis?"
2. "Does my deductible apply to this drug?"
3. "Is it a copay or coinsurance? What's the dollar estimate per fill right now?"
4. "How much of my out-of-pocket maximum is left?"
5. "Do manufacturer savings card payments count toward my deductible?"

To decode tiers and restriction codes, see how to read a formulary. If you're choosing a plan, the open enrollment questions turn this math into a comparison sheet. For the bigger picture on how cost shapes treatment, read why affordability can change the whole journey.

Common questions

Why is my GLP-1 so expensive if insurance covers it?

Usually because your deductible applies to the drug, or because you owe coinsurance (a percentage) instead of a flat copay. Early in the plan year you may be paying the full negotiated price until the deductible is met.

Does a GLP-1 copay count toward my out-of-pocket maximum?

In-network cost-sharing for covered drugs generally counts. Premiums, drugs your plan doesn't cover and out-of-network costs don't. Manufacturer card payments may or may not count, depending on your plan.

What's the out-of-pocket limit for 2026?

For ACA-compliant plans, the 2026 in-network limit is $10,600 for an individual and $21,200 for a family. Many plans set lower limits.

Can I use a manufacturer savings card on Medicare?

Generally no. Manufacturer card terms exclude people with government coverage like Medicare and Medicaid.