Deductibles, coinsurance, and out-of-pocket maximums work together much like filling a bucket. First, you pay the deductible (the bottom half of the bucket) entirely on your own. Once the deductible is met, coinsurance begins, where you and the insurance company share the costs (the upper half of the bucket). After reaching your out-of-pocket maximum, your insurance plan covers all further in-network care for the rest of the year.