Health · Chapter 15 · Cost Sharing
Coinsurance (Percentage Participation)
Definition
After the deductible, insurer and insured split covered costs by percentage (insurer/insured — 80/20 is classic). Exists to discourage overutilization. Courses teach that a plan paying less than 50% is treated as a discount plan, not insurance.
In plain English
$1,500 bill, $500 deductible, 80/20: you pay $500 + 20% of $1,000 = $700; insurer pays $800.
Exam tip
Exam math shortcut: ALWAYS compute the insured's share first (deductible + their percentage), then subtract from the total for the insurer's share.
Easy to confuse with
These are what this term gets tested against — if you can't tell them apart cold, drill the contrast.
Related terms