Your insurance has an advertised price for a procedure saying “we will pay upto X price”. If the doctor thinks “well that’s a fair price” then they accept the insurance. If not, they don’t.
Sometimes they’ll ask you to cover the difference between what insurance will pay and what the doctor charges.
These are different from co-pays, which the insurance expects you to pay before the insurance pays, meaning you pay no matter how much the insurance covers, even all of it.
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