Two issues - first, it sounds like your provider billed you in advance. Merit Health and others do this. I had a visit there and they DEMANDED i pay my $1000 deductible and estimated 20% copay before they'd admit me. Even though they could clearly see on their system that my deductible had been met. Bottom line, they want to keep what they can and apply that to my coinsurance payment after discharge and then simply send me the difference as a credit because they know they're getting paid up front and won't have to worry about billing me after the procedure and then waiting for their money. It sucks, but they can do it. SECONDLY and more importantly, it sounds like you were balanced billed - in fact, i'm willing to bet money. It's illegal and most medical providers aren't even aware of it. Bottom line, if your doctor accepts an assignment of benefits, directing your insurer to pay them directly (which they all do), then they CANNOT bill you for more than your deductible and coinsurance. What happens is many ancillary services (xray, lab, and sometimes the doctor's fee) are contracted to others who are not in-net work with your insurer (the hospital may be in net work, but a lot of people working inside that hospital are not hospital employees and they bill separately for their services). THEY ALL DO THIS. It's part of the new healthcare model at most hospitals. Well in that case, the radiologist or lab may be out of network and they're trying to bill you for what your insurance didn't pay. That's illegal - see Ms. HB95 from the 2020 legislative session which gives the Dept of Insurance authority to step in when that happens. The Commissioner has been all over talk radio for the past 2 years talking about how prevalent it is. To see if it happened, look at your EOB. If it was denied as "out of network" yet your doctor or hospital were in net-work, then there's your answer. Call them up and tell them to see HB95 and zero balance you.