insurance

Co-Insurance

A cost-sharing arrangement where the insured pays a specified percentage of covered medical expenses after meeting their deductible. The insurance company pays the remaining percentage until the out-of-pocket maximum is reached.

Example

“After meeting her $2,000 deductible, Maria's health plan required 20% co-insurance, meaning she paid $400 of her $2,000 surgery while her insurer covered the remaining $1,600.”

Memory Tip

Think 'co' as in 'cooperation' - you and your insurer cooperate to split the bills after your deductible.

Why It Matters

Co-insurance directly affects your healthcare costs and budgeting since you'll pay a percentage of every medical bill after your deductible. Understanding your co-insurance rate helps you estimate potential medical expenses and choose between insurance plans with different cost-sharing structures.

Common Misconception

Many people confuse co-insurance with copayments, thinking they're the same thing. Unlike copayments which are fixed dollar amounts, co-insurance is a percentage of the total cost, meaning your out-of-pocket expense varies with the size of the medical bill.

In Practice

If you have a health plan with a $1,500 deductible and 25% co-insurance, here's how a $10,000 hospital stay works: You first pay the $1,500 deductible. Of the remaining $8,500, you pay 25% ($2,125) and your insurer pays 75% ($6,375). Your total cost would be $3,625 ($1,500 deductible + $2,125 co-insurance). This continues until you reach your plan's out-of-pocket maximum, after which the insurer pays 100%.

Etymology

From the prefix 'co-' meaning 'together' and 'insurance,' reflecting the shared financial responsibility between insurer and insured that became standard in health insurance during the mid-20th century.

Common Misspellings

coinsuranceco-insurencecoin-suranceco-ensurance

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Other insurance terms you should know

deductibleThe amount you pay out-of-pocket before your insurance begin…insurance premiumThe amount paid periodically to an insurance company in exch…deductibleThe amount a policyholder must pay out of pocket before insu…copayA fixed amount paid by an insured person at the time of a me…coinsuranceA cost-sharing arrangement where the insured pays a percenta…out-of-pocket maximumThe most an insured person will pay for covered healthcare s…