Medicaid paid only part of my hospital bill. Can the hospital bill me for the rest?

Federal rules answer most of this. A state plan must limit who takes part in Medicaid [1]. It must limit it to providers who accept the state payment as payment in full [1]. In full means the amount the agency pays [1]. It also means any deductible, coinsurance or copayment the plan makes you pay [1]. So the hospital charge above that payment is not your bill, apart from the cost sharing the rules allow [1][2].

One part can still be yours. That part is the cost sharing. The rule says that not being able to pay does not wipe out what you owe for it [1]. Note what these sources cover. They cover a provider in the Medicaid program, and cost sharing set by the state plan. They do not say what you owe for a service Medicaid did not cover. They do not say what you owe for care on a day you were not eligible.

Cost sharing has a limit of its own. As a rule, no provider may deny you services because you cannot pay the cost sharing [2]. One paragraph holds the exception. The agency may let a provider ask for the cost sharing first [2]. That is allowed if three things are true. Your family income is above 100 percent of the FPL [2]. You are not part of an exempted group [2]. And for care that is not an emergency in an emergency room, other conditions are met [2].

Check two facts first. Was the provider in the Medicaid program on that date? Were you eligible that day? Your state Medicaid agency can confirm both. Then read 42 CFR 447.15 and the payment in full line [1], and 42 CFR 447.52(e) for the cost sharing exception [2]. Whether your state also limits what the provider may charge: "Don't know yet" here.