UnitedHealthcare, Aetna Medicare, and Humana saw the largest enrollment gains during the 2020 Medicare Annual Election Period, increasing their enrollments by 8.3%, 16.7%, and 5.2% respectively. Many top plans focused their direct mail marketing campaigns on supplemental benefits like dental, vision, hearing and transportation assistance to differentiate themselves. Additional factors beyond marketing also influence enrollment growth, such as market competition, broker incentives, and plan benefits.