Is coinsurance calculated on the whole claim?

No, on what remains after the deductible. Twenty percent coinsurance on a 450,000 claim with a 25,000 deductible is twenty percent of 425,000, not of 450,000.

What does the out of pocket maximum do?

It caps everything you pay in the year. On a catastrophic claim it is the most valuable feature of the policy, because unbounded coinsurance on a large claim is a large bill.

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Copay and Coinsurance Calculator

What you pay on a claim after deductible, coinsurance and copay. The order matters: the deductible comes off first and coinsurance applies only to what remains, not to the whole claim.

Also called: coinsurance calculator, health claim cost share.

You pay

$5,200.00

$5,200.00 of a 18,000 claim: $2,000.00 deductible, $3,200.00 coinsurance and $0.00 copay, capped at the 8,000 out of pocket maximum. The insurer pays $12,800.00. This claim did not reach the out of pocket maximum.

Insurer pays

$12,800.00

Deductible

$2,000.00

Coinsurance

$3,200.00

Copay

$0.00

Your effective share

28.89%

What you would pay without the cap

$5,200.00

On the out of pocket maximum

This claim did not reach the out of pocket maximum.

How this is calculated

An estimate, not an offer or a guarantee. Projected returns assume the rate you entered holds for the whole term, which no market does.

Method and background

This is what the calculation gives for the numbers you entered. It is an estimate, not advice, and it knows nothing about your situation beyond those numbers. Rules for United States change on a published schedule; the effective date is shown on every rule-based tool.

How this is calculated

Three cost-sharing mechanisms stack in order. The deductible is paid in full first. Coinsurance is your percentage of what remains after it, not of the whole claim, which is the step most often computed wrongly. A fixed copay adds on top. The out of pocket maximum caps the total, and it is the most valuable feature of the policy on a large claim: without it, twenty percent coinsurance on a catastrophic claim is a catastrophic bill.

the deductible comes off first, then coinsurance applies only to the remainder

D: Deductible
c: Coinsurance rate

Worked examples

Each of these is asserted on every build. If a change to the engine ever moved one of these answers, the build would fail before the page could print it.

an 18,000 hospital claim

Claim amount: $18,000.00
Deductible: $2,000.00
Coinsurance share you pay: 20%
Fixed copay per claim: $0.00
Out of pocket maximum: $8,000.00
Plan maximum: $1,000,000.00

You pay$5,200.00

The deductible comes off first, so coinsurance is 20% of the remaining 16,000 = 3,200, not 20% of 18,000. Getting that order wrong overstates the bill by 400.

Open this example

a large claim hits the cap

Claim amount: $60,000.00
Deductible: $2,000.00
Coinsurance share you pay: 20%
Fixed copay per claim: $0.00
Out of pocket maximum: $8,000.00
Plan maximum: $1,000,000.00

You pay$8,000.00

boundary: 2,000 plus 20% of 58,000 would be 13,600, but the out-of-pocket maximum binds first and stops it at 8,000. This is the number that makes a plan comparable.

Open this example

Method and limits

What it assumes

A single claim within the policy year.

What it deliberately does not model

Out of network care often has a separate and much higher maximum, or none.
Some services are excluded from the deductible or from the maximum.
The maximum usually resets annually, so a claim spanning a year boundary can hit it twice.

Formula version 1.0.0 · definition 1.0.0 · United States · Report a problem with this calculator

Frequently asked questions

Is coinsurance calculated on the whole claim?: No, on what remains after the deductible. Twenty percent coinsurance on a 450,000 claim with a 25,000 deductible is twenty percent of 425,000, not of 450,000.
What does the out of pocket maximum do?: It caps everything you pay in the year. On a catastrophic claim it is the most valuable feature of the policy, because unbounded coinsurance on a large claim is a large bill.