If your insurance pays their negotiated rate for a service, can the doctor then charge you the difference? I didn't think they could, but wanted to make sure. We had an insurance mix-up with my son's dentist appt and the insurance finally paid their negotiated rate, which is about $11 less than the billed amount. The dentist office told me there was an 'outstanding amount due' and I want to know the facts before I complain about this. I told them it was due to the negotiated rate and they said they'd look into it, but knowing them, they won't and this issue will come up again. I've *never* had a medical provider try to charge me the difference between amount charged and negotiated/contract price!