Customary Fee
Most insurance plans will pay only what they call a reasonable and customary fee for a particular service. If your doctor charges $1,000 for a hernia repair while most doctors in your area charge only $600, you will be billed for the $400 difference. This is in addition to the deductible and coinsurance you would be expected to pay. To avoid this additional cost, ask your doctor to accept your insurance company's payment as full payment. Or shop around to find a doctor who will. Otherwise you will have to pay the rest yourself.