Quick answer
Coinsurance is the percentage of a covered medical bill you pay after you’ve met your deductible. With 20% coinsurance, you pay $200 of a $1,000 covered bill and your plan pays $800. You keep paying coinsurance until you reach your plan’s out-of-pocket maximum, and then the plan pays 100% of covered in-network care for the rest of the year.
Key takeaways
- Coinsurance is a percentage of the bill. A copay is a flat dollar amount.
- It usually starts after you meet your deductible, and it counts toward your out-of-pocket maximum.
- 20% and 30% are common rates. Plans with lower premiums tend to have higher coinsurance.
- Because it’s a percentage, coinsurance on expensive care like surgery or a hospital stay adds up fast.
- Out-of-network coinsurance is usually higher, and some out-of-network costs don’t count toward your limit.
On this page
How coinsurance works
Here’s an example with a $1,500 deductible, 20% coinsurance and a $6,000 out-of-pocket maximum:
| Bill | You pay | Your plan pays |
|---|---|---|
| First $1,500 of covered care | $1,500 (your deductible) | $0 |
| $10,000 hospital stay after that | $2,000 (20%) | $8,000 |
| $15,000 more care later in the year | $2,500, which gets you to the $6,000 limit | $12,500 |
| Any more covered in-network care that year | $0 | 100% |
Coinsurance often applies to hospital stays, surgery, imaging like X-rays, lab work and some prescription drugs. Many plans use flat copays for routine office visits instead, and emergency room visits may come with a copay, coinsurance or both.
The percentage is applied to your plan’s negotiated rate, so make sure your doctor is in network. Out of network, you may pay a higher percentage of a higher price.
Coinsurance vs. copays
| Coinsurance | Copay | |
|---|---|---|
| What it is | A percentage of the bill | A flat dollar amount |
| When it usually applies | After the deductible | Often from the first visit |
| Example | 20% of a $400 visit = $80 | $30 per visit |
| Easy to predict? | Harder, since it depends on the bill | Yes |
Most plans use both: copays for everyday care and coinsurance for bigger services. See what a copay is and whether copays count toward your deductible. Almost every kind of health plan uses coinsurance in some form; our guide to health insurance coverage types compares them.
Coinsurance and your deductible
Coinsurance usually doesn’t start until you’ve paid your deductible. Before that, you pay the full negotiated price for most services. Plans trade these pieces off against each other: a higher deductible and higher coinsurance usually mean a lower premium. How you meet your deductible shows what counts toward it.
On marketplace plans, the metal level tells you roughly how costs are shared. A bronze plan pays about 60% of an average enrollee’s covered costs, silver about 70%, gold about 80% and platinum about 90%.
The out-of-pocket maximum caps it
Coinsurance can’t go on forever. Deductibles, copays and coinsurance for covered in-network care all count toward your out-of-pocket maximum, which can be no more than $10,600 for one person and $21,200 for a family in 2026, or $12,000 and $24,000 in 2027. Once you reach it, the plan pays 100% of covered in-network care for the rest of the year. See what an out-of-pocket maximum is.
Choosing a plan with coinsurance in mind
If you expect expensive care this year, such as surgery, a baby or ongoing treatment, look past the premium at the coinsurance rate and the out-of-pocket maximum. A plan with 0% or 10% coinsurance can save you thousands. If you rarely see a doctor, higher coinsurance in exchange for a lower premium can work, as long as you could cover the out-of-pocket maximum.
When you compare plans, check several insurers, and be honest about whether you could handle a big bill out of pocket.
See each plan’s coinsurance and out-of-pocket limit: compare plans in your ZIP code.
Frequently asked questions
Does coinsurance count toward my out-of-pocket maximum?
Yes, for covered in-network care. Once your deductible, copays and coinsurance add up to the limit, you stop paying for covered in-network care that year.
Do I pay coinsurance before I meet my deductible?
Usually not. Before the deductible, you typically pay the full negotiated rate. A few services may have copays or coinsurance from the start, depending on the plan.
What does 0% coinsurance mean?
After you meet the deductible, the plan pays 100% of covered care. You may still owe copays for some services.
Is 20% coinsurance good?
It’s common. Whether it’s a good deal depends on the premium, deductible and out-of-pocket maximum that come with it.
Sources
This article is general information, not insurance advice. Cost-sharing rules vary by plan, so check your plan’s summary of benefits or ask your insurer. Last reviewed September 2026.