No. A hospital in New Jersey can be in-network for insurance purposes, but specialists performing individual items of work can be out of network and can balance bill you. That being said, I don't know your particular facts and I must guess. You went in for heart surgery at a hospital that is in-network for your insurance. A cardiologist specializing in a certain facet of your heart had to be consulted, He charges $500 for that consultation. The surgery is all covered but the $500 bill arrives at your door.
Otherwise, balance billing is very illegal in New Jersey. An in network provider cannot accept a payment from you insurer and then send you a supplemental bill for additional funds.
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