A deductible is the amount you pay for health care services each year before your health insurance begins to pay. The higher a plan’s deductible, the lower the premium. The lower a plan’s deductible, the higher the premium. You’ll pay more each month, but your plan will start sharing the costs sooner because you’ll reach your deductible faster.
A copay is the fixed amount you pay for a covered health care service like an office visit or pick up prescription drugs after you've paid your deductible.
A coinsurance is a set percentage the customer pays for a covered service. For instance, a copay for a doctor’s visit may be $25, you would pay a $25 copay for each visit to your doctor. On the other hand a coinsurance for a similar visit could be 30% and if a doctor’s appointment costs your insurance company $100, then you would owe $30 at the time of your visit.
An out-of-pocket maximum is the amount that you reach that amount you will not have to pay anymore out-of-pocket for covered care for the rest of the year – this includes coinsurance and copay.
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