Short answer: Yes. Medicare Advantage plans must write into their provider contracts that enrollees eligible for both Medicare and Medicaid are not liable for Part A and B cost-sharing when the state is responsible for it.
Under 42 CFR 422.504(g)(1)(iii), every Medicare Advantage organization with enrollees eligible for both Medicare and Medicaid must specify in its provider contracts that those enrollees won’t be held liable for Medicare Part A and B cost-sharing when the state is responsible for paying it. The plan also can’t impose cost-sharing above what Medicaid would allow for that person.
So when the state is responsible for a QMB member’s Medicare cost-sharing, the plan’s Part A and B copays generally can’t be collected from that member at the doctor’s office. Medicare.gov’s advice for a QMB member in a Medicare Advantage plan who is being billed: contact the plan and ask it to stop the charges.