The Three Terms on Almost Every Health Insurance Bill
If you've ever stared at an Explanation of Benefits and wondered why you still owe money after having insurance, you're not alone. Deductibles, copays, and coinsurance are the three main ways insurers share costs with you — and each one works differently. Knowing what each term means before you get care can prevent sticker shock when the bill arrives.
| What a deductible resets | Annually, at the start of each plan year |
| Typical copay range (primary care) | $10–$50 per visit (Varies widely by plan and region) |
| Common coinsurance split | 80% insurer / 20% enrollee (Exact split depends on individual plan) |
| When coinsurance applies | After the deductible is met |
| Out-of-pocket maximum purpose | Caps your total annual cost-sharing exposure (ACA-compliant plans must include this limit) |
These concepts apply broadly across health insurance plans — employer-sponsored, marketplace, and Medicare supplement plans alike. Coverage details, exclusions, and exact amounts vary by policy, so always read your plan documents or ask a licensed insurance agent about your specific plan. This article provides general education, not personalized insurance or financial advice.
Deductible: What You Pay First
A deductible is the amount you pay entirely out of pocket for covered services before your insurer starts sharing costs. If your plan has a $1,500 deductible, you pay the first $1,500 of covered medical expenses yourself each plan year. Only after that threshold is met does the insurance company begin contributing.
A few important nuances:
- Not every service counts toward the deductible. Many plans cover preventive care — annual physicals, certain screenings — before the deductible is met. Check your Summary of Benefits.
- Family plans often have two deductible thresholds — an individual limit and a family limit. Either can trigger insurer cost-sharing depending on your plan design.
- In-network vs. out-of-network deductibles are sometimes separate and the out-of-network amount is typically higher.
For a plain-language look at how deductibles appear in auto coverage as well, see how deductibles work in car insurance.
Copay: A Fixed Fee at the Time of Service
A copay (short for copayment) is a flat dollar amount you pay for a specific service at the time you receive it — regardless of the total cost of that service. Common examples: $25 for a primary care visit, $50 for a specialist, $10 for a generic prescription.
Copays are predictable by design. You know the amount upfront, and it doesn't change based on what the provider charges. However:
- Copays may or may not count toward your deductible, depending on your plan.
- Some services — like emergency room visits or certain specialist consults — carry higher copays.
- After you hit your out-of-pocket maximum, copays typically no longer apply for the rest of the plan year.
For a side-by-side look at how copays and coinsurance calculate differently, see how copays and coinsurance compare.
Coinsurance: Your Percentage After the Deductible
Coinsurance is the percentage of costs you share with your insurer after you've met your deductible. A common split is 80/20 — your insurer covers 80% of the allowed amount for a covered service, and you pay the remaining 20%.
Unlike a copay, coinsurance is not a fixed dollar amount. It scales with the total cost of care, which means a high-cost procedure produces a much larger coinsurance bill.
Example: You've met your deductible. Your plan has 20% coinsurance. You receive an in-network service with an allowed cost of $2,000. Your insurer pays $1,600; you owe $400.
Coinsurance Scales With Cost of Care
Because coinsurance is a percentage, the dollar amount you owe grows with the price of the service. A 20% share of a $500 procedure is $100 — but 20% of a $10,000 surgery is $2,000. This is why knowing your out-of-pocket maximum matters so much for expensive or unexpected care. Always confirm what counts toward that cap under your specific plan.
Coinsurance stops accumulating once you reach your plan's out-of-pocket maximum — after that point, covered in-network services are generally paid in full by the insurer for the rest of the plan year. That cap is one of the most important numbers in your policy. You can find more policy terminology explained in the Policy Terms Explained hub.
Putting It All Together: How the Three Interact
These three cost-sharing mechanisms usually operate in sequence during a plan year:
- You pay the deductible first. Until it's met, you cover 100% of most covered services.
- Coinsurance kicks in after the deductible. You and the insurer split costs according to your plan's percentage.
- Copays may apply at any stage — often before the deductible is met — for specific service categories like office visits or prescriptions, depending on how your plan is structured.
- Everything stops at the out-of-pocket maximum. Once your deductible, coinsurance, and copays add up to the plan's annual cap, the insurer covers 100% of covered in-network costs for the remainder of the year.
If managing what you owe across the year feels complicated, strategies for keeping out-of-pocket costs manageable can help you think through options like timing elective care or using in-network providers consistently.
Deductible
The amount you pay out of pocket for covered services before your insurer begins sharing costs. Resets each plan year.
Copay
A fixed dollar amount you pay for a specific covered service at the time you receive it, such as $25 for a doctor visit. The amount is set by your plan and does not vary with the provider's charge.
Coinsurance
Your share of costs expressed as a percentage after your deductible is met. For example, 20% coinsurance means you pay one-fifth of the insurer's allowed amount for a covered service.
Out-of-Pocket Maximum
The most you will pay for covered in-network services in a plan year. Once this cap is reached, the insurer generally pays 100% of covered costs for the rest of the year.
Allowed Amount
The maximum dollar amount your insurer has agreed to pay for a covered service from an in-network provider. Coinsurance percentages are calculated against this figure, not the provider's billed charge.
Explanation of Benefits (EOB)
A statement from your insurer showing what was billed, what the insurer paid, and what you owe after a claim is processed. It is not a bill, but it helps you verify charges.
This article is for general informational and educational purposes only. It is not personalized insurance, financial, or legal advice. Coverage terms, amounts, and rules vary by plan and provider. Read your policy documents carefully and consult a licensed insurance agent or advisor for guidance specific to your situation.
