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How to Appeal a Medicare Claim Denial Decision
In addition, Medicare Advantage companies must give patients a way to report grievances about the plan and the quality of care they receive from providers in the plan. If you have a Medicare Advantage plan, look at your plan materials or contact the plan administrator for information about filing a grievance or an appeal. For more details, see the Medicare publication “Your Medicare Rights and Protections” or "Medicare Advantage Plans and Medicare Cost Plans: How to File a Complaint (Grievance or Appeal)."