| Premium | Fixed monthly (or annual) cost to maintain coverage |
| Deductible | Amount you pay before insurer shares costs |
| Copay | Flat fee paid at the time of a specific service |
| Coinsurance | Percentage of costs you share after the deductible is met |
| Out-of-Pocket Maximum | Annual cap on total cost-sharing; insurer covers 100% beyond this |
| Typical coinsurance split | 80/20 (insurer/patient) is a common structure (Common industry standard; varies by plan) |
Why These Four Terms Matter
When you open an insurance bill or compare health plans during open enrollment, four words keep showing up: premium, deductible, copay, and coinsurance. Together, they control virtually everything you pay — both before and after you file a claim. Misread any one of them and you can end up with a plan that looks affordable until something actually happens.
This reference breaks each term down to its plain meaning, shows how they interact, and flags the common confusion points that cost people money. For a broader look at policy vocabulary, see our plain-language insurance glossary.
| Premium | Fixed monthly (or annual) cost to maintain coverage |
| Deductible | Amount you pay before insurer shares costs |
| Copay | Flat fee paid at the time of a specific service |
| Coinsurance | Percentage of costs you share after the deductible is met |
| Out-of-Pocket Maximum | Annual cap on total cost-sharing; insurer covers 100% beyond this |
| Typical coinsurance split | 80/20 (insurer/patient) is a common structure (Common industry standard; varies by plan) |
This article is general educational information, not personalized financial, insurance, or legal advice. Coverage terms, amounts, and rules vary by policy and state. Always read your actual policy documents and consult a licensed insurance agent or adviser for guidance specific to your situation.
The Four Terms, One by One
Premium
Your premium is the fixed amount you pay to keep your policy active — typically monthly, though some plans bill quarterly or annually. You owe it whether or not you ever use the insurance. Think of it as a membership fee: pay it and the coverage stays on; miss it and the insurer can cancel the policy.
Deductible
Your deductible is the dollar amount you must pay out of pocket for covered services before your insurer starts sharing costs. If your health plan has a $1,500 deductible, you cover the first $1,500 in eligible claims each policy year. After that threshold is met, the insurer begins to pay its share. Some services — like preventive care on many health plans — may apply before the deductible is met, so check your plan details.
Copay
A copay (short for copayment) is a flat dollar amount you pay at the time of a specific service — say, $30 for a primary-care visit or $15 for a generic prescription. Copays are predictable by design. Depending on your plan, copays may count toward your deductible or your out-of-pocket maximum, but not always. Read your Summary of Benefits and Coverage to confirm.
Coinsurance
Once your deductible is satisfied, coinsurance kicks in. Instead of a flat fee, coinsurance is a percentage split between you and the insurer. A common structure is 80/20: the insurer pays 80% of covered costs and you pay 20%. That 20% continues until you hit your plan's out-of-pocket maximum — the ceiling on what you can owe in a policy year. After that, the insurer covers 100% of covered costs for the remainder of the year.
Premium
The regular payment — usually monthly — you make to keep an insurance policy active. It is owed regardless of whether you use the coverage.
Deductible
The dollar amount you must pay for covered services in a policy year before your insurer begins contributing. Applies separately to each new policy period.
Copay (Copayment)
A fixed dollar amount due at the time of a covered service, such as a doctor visit or prescription pickup. The amount is set by your plan and listed in the Summary of Benefits.
Coinsurance
A percentage of covered costs you pay after your deductible is satisfied. For example, 20% coinsurance means you pay one-fifth of the allowed amount while the insurer covers the rest.
Out-of-Pocket Maximum
The most you can be required to pay in covered costs within a single policy year. Once reached, the insurer generally pays 100% of covered in-network expenses for the remainder of the year.
Allowed Amount
The maximum dollar figure an insurer agrees to pay for a covered service from an in-network provider. Any balance above this amount may not count toward your deductible or coinsurance.
How the Four Terms Work Together
These terms rarely act in isolation. Here's a simplified sequence for a typical health insurance claim:
- You pay your premium every month to stay covered.
- You receive care. If you owe a copay, you pay it at the visit. Some plans apply the copay regardless of whether you've met your deductible.
- Your claim is processed. If your deductible isn't yet met, you pay the full allowed amount for that service. Copays often count toward this total — confirm with your plan.
- Once the deductible is met, coinsurance applies. You pay your percentage share; the insurer pays the rest.
- Once you hit your out-of-pocket maximum, the insurer covers 100% of covered in-network costs for the rest of that policy year.
The same basic framework applies in other insurance lines. Auto insurance deductibles work similarly — you pay the deductible when you file a collision or comprehensive claim, and the insurer covers the remainder up to your policy limits. See how auto coverage types interact with these costs for more detail.
Don't Forget the Out-of-Pocket Maximum
Every cost-sharing plan is required by the Affordable Care Act to include an out-of-pocket maximum for most individual and group health plans. For 2024, the federal limit for in-network costs is $9,450 for an individual and $18,900 for a family. This cap applies to deductibles, copays, and coinsurance combined — but generally not to premiums or out-of-network charges. Check your specific plan documents for the exact figure that applies to you.
For a deeper look at how these cost structures play out across different plan types — HMOs, PPOs, and HDHPs — visit our health insurance coverage types guide.
Common Confusion Points
Low premium ≠ low cost. Plans with lower monthly premiums almost always carry higher deductibles and coinsurance. If you rarely use care, that trade-off may work in your favor. If you have ongoing medical needs, a higher premium with lower cost-sharing could save money overall. Neither outcome is guaranteed — run the math using your anticipated usage before choosing.
Copays and deductibles aren't always separate. Some plans count copays toward the deductible; others don't. This distinction significantly affects how quickly you reach your deductible in a high-use year.
Family plans often have two deductibles. Many family health plans carry both an individual deductible and a family aggregate deductible. Once the family aggregate is met, no individual in the plan needs to keep meeting their own deductible for the year.
Out-of-network care changes everything. Deductibles, copays, and coinsurance percentages are often different — and far less favorable — when you see providers outside your plan's network. Always verify network status before a non-emergency visit.
When comparing plans, reading the declarations page carefully helps you spot exactly where these numbers appear in your policy documents.
$1,644
Average individual health insurance deductible (employer-sponsored plan)
According to the Kaiser Family Foundation 2023 Employer Health Benefits Survey, the average single-coverage deductible for workers with a deductible was approximately $1,644.
~83%
Workers enrolled in plans with a general annual deductible
The Kaiser Family Foundation 2023 Employer Health Benefits Survey found that roughly 83% of covered workers faced a general annual deductible for single coverage.
20%
Common patient coinsurance share after deductible
A 80/20 cost-sharing split — where the patient pays 20% and the insurer pays 80% after the deductible — is a widely used coinsurance structure in the US market.