What Does 0% Coinsurance After Deductible Mean?

Last reviewed: October 6, 2026.

If your plan summary says "0% coinsurance after deductible," you are looking at one of the friendlier lines on the page. It tells you what happens once you have paid your share of the first dollars of care. This guide explains the phrase in plain English, shows the math on a real-sized bill, and lists what a 0% line does not cover.

What is coinsurance in health insurance?

Coinsurance is the percentage of a covered health care cost that you pay after you have met your deductible. HealthCare.gov defines it as the percentage of costs of a covered service you pay, such as 20%, after you have paid your deductible (HealthCare.gov, 2026).

A deductible is the amount you pay for covered care each year before your plan starts sharing costs. So the order is simple: you pay the deductible first, then you and the plan split the next costs by the coinsurance percentage.

What does 0% coinsurance after deductible mean?

It means your share of the split is zero. After you meet the deductible, the plan pays 100% of the allowed amount for covered in-network services, and your coinsurance bill is $0 (HealthCare.gov, 2026).

The "allowed amount" is the price your plan has agreed to pay for a service. Your plan pays against that price, not against whatever a provider chooses to charge.

Here is the same $12,000 hospital bill (allowed amount) under four plan setups. This is an illustration, not a real plan, and it leaves out copays and premiums.

The first row comes from the HealthCare.gov example: a $3,000 deductible plus 20% of the remaining $9,000, which is $1,800, for $4,800 in total (HealthCare.gov, 2026). Change the coinsurance to 0% and the $1,800 disappears.

Does 0% coinsurance mean everything is free after the deductible?

No. A 0% coinsurance line only removes the percentage you pay on covered, in-network services. Four things can still cost you money.

• Your monthly premium. The out-of-pocket limit never includes premiums (HealthCare.gov, 2026).
• Copays. A plan can charge a flat copay for a visit or a prescription even when coinsurance is 0%. Check each line of the summary of benefits.
• Out-of-network care. The out-of-pocket limit does not count out-of-network care or charges above the plan's allowed amount (HealthCare.gov, 2026).
• Services the plan does not cover. You pay those in full.

Think of 0% coinsurance as one dial on the plan, not a guarantee that a bill will be zero.

How does 0% coinsurance work with the out-of-pocket maximum?

The out-of-pocket maximum is the most you pay in a year for covered in-network care. After you reach it, the plan pays 100% of covered benefits (HealthCare.gov, 2026). The limit counts deductibles, copayments and coinsurance, but not premiums.

For Marketplace plans, the limit is $10,600 for one person and $21,200 for a family in 2026, and $12,000 and $24,000 in 2027 (HealthCare.gov, 2026). The 2027 figures come from the federal Notice of Benefit and Payment Parameters that CMS issued on January 29, 2026, as summarized by Milliman (2026).

With 0% coinsurance, the deductible is your main cost for a big claim. You will usually hit your deductible long before you hit the out-of-pocket maximum, so the maximum matters mostly as a safety net.

Is a plan with 0% coinsurance worth a higher premium?

It can be, but only when the extra premium costs less than the coinsurance you expect to avoid. Add the 12 months of premiums to your likely out-of-pocket spending for each plan and compare the totals.

Here is a hypothetical comparison. The premiums are made up for the example and are not quotes. Both plans have a $3,000 deductible.

Plan B costs $960 more in a healthy year and $840 less in a year with a large claim. If you expect surgery, a pregnancy, or ongoing treatment, the 0% plan starts to look better. If you rarely use care, the lower premium usually wins.

The same logic applies to a $0 deductible plan. Summit's guide to $0 deductible health insurance walks through that tradeoff.

How do deductible, copay and coinsurance fit together?

They are three different ways a plan splits a bill with you. The deductible comes first, the copay is a flat fee for a specific service, and coinsurance is a percentage of the allowed amount.

A plan can mix these by service. One plan might charge a copay for primary care, apply the deductible and then 0% coinsurance to hospital stays, and apply 20% to imaging. Read each line instead of assuming one number covers the whole plan.

Where do the costs of a hospital stay show up?

A hospital stay is where coinsurance matters most, because the allowed amount is large. If your plan has 20% coinsurance, even a modest bill leaves you paying a percentage on top of the deductible.

To see typical hospital price ranges, read Summit's breakdown of how much a hospital stay costs. Then apply your own plan's deductible and coinsurance to those numbers.

Who helps you compare plans and coverage options?

You can compare plan summaries yourself, or ask an advisor to line them up for you. Either way, ask for the deductible, the coinsurance by service, the copays, the out-of-pocket maximum and the network.

Summit Health Benefits offers a Health Membership for Individuals and Families. It includes virtual urgent care, virtual primary care, a prescription program and a HealthShare feature with a $2,500 out-of-pocket cap per need (Summit Health Benefits, 2026). The cap applies to each need, not to the whole year. Membership is not insurance, and it does not guarantee payment of medical bills.

Some households use a membership like this when marketplace premiums do not fit the budget. Others keep insurance and add the membership for everyday care. Summit's guide to health share pros and cons explains the tradeoffs, including what a share program does not promise.

If you need a marketplace plan, the dates matter. See open enrollment dates and changes and the rules for a special enrollment period.

How do you check your own plan for 0% coinsurance?

Open your Summary of Benefits and Coverage and follow five steps.

1. Find the annual deductible for you and for your family.
2. Look at the common medical events table and read the coinsurance or copay for each service.
3. Note which services say "deductible applies" and which say "no charge."
4. Find the out-of-pocket maximum, and check whether it covers in-network care only.
5. Add 12 months of premium to your expected spending and compare plans.

If a line says "0% coinsurance after deductible," you owe nothing more on that service once the deductible is met, apart from any copay listed.

Frequently Asked Questions

Sources: HealthCare.gov, Glossary: Coinsurance and Out-of-Pocket Maximum/Limit (2026); Milliman, 2027 ACA Out-of-Pocket Maximum Limits Released, citing the CMS HHS Notice of Benefit and Payment Parameters (January 29, 2026); Summit Health Benefits, Health Membership for Individuals and Families plan page (2026).