A hospital that takes Medicare bills Medicare first. That is the deal it signed. Your share does not exist yet; it is whatever is left after Medicare decides. Say it, in writing if you can: "Please bill Medicare and send me the statement once it is processed." Then wait for the Medicare Summary Notice, the paper Medicare mails you that says what you actually owe. In an emergency they treat you first. Federal law. The bill comes after. Hospitals can ask; they cannot make paying first a condition of being admitted. A doctor's office is different and can collect at the visit.
On Medicare and the hospital wants payment first? Upload the bill and the Medicare Summary Notice. This checks them against each other.
Check your bill — freeThe check is free. The letter is the paid part: you print and mail it yourself, or we send it by certified mail for you. No account needed to start.
This is the general rule, in plain words. BillFighter is not a law firm and does not give legal advice. If you have been served with court papers, that is the day for a lawyer or legal aid.