Question
What is the name of your state? MA.
Often after I've had a doctor visit I get billed in addition to my copay an amount that the insurnace company apparently didn't pay. Can the doctor do this? If so, then what's the point of a copay? I thought the copay was all I had to pay for the visit?
Answer
Whether he can or can't depends on the type of policy you have and the reason the insurance carrier didn't pay it.
If it was not paid because it's not a covered benefit under the policy, you owe it. If it was not paid because it is over and above the amount the insurance carrier will pay for that procedure, you might or might not have to pay it depending on the terms of your insurance plan.
Answer
What is the name of your state? MA.
Often after I've had a doctor visit I get billed in addition to my copay an amount that the insurnace company apparently didn't pay. Can the doctor do this? If so, then what's the point of a copay? I thought the copay was all I had to pay for the visit?
In addition to what cbg stated, take a look at your explanation of benefits (EOB) your insurance company sends you. The amount listed in the "subscriber liability" is the amount you owe. The Doctor can bill you for the remainder ONLY if h/she is not on contract (in network) with your insurance company.