Nearly all of the 55 million Medicare beneficiaries enrolled in Part D plans are overpaying by thousands of dollars yearly, due to choosing plans based on monthly premiums. Data shows 95% overspend, highlighting the importance of considering total annual costs when selecting a plan.

Part D plans cover prescription drug costs, including recommended vaccines, and are run by private insurance companies following Medicare guidelines. Enrollment data from KFF in 2025 shows 54.8 million beneficiaries in Part D plans, with 58% in Medicare Advantage and 42% in standalone plans.

Enrollment is dominated by five firms covering 73.5% of Part D enrollees, with a base premium of $36.78 and a maximum out-of-pocket deductible of $590 in 2025. Choosing a plan solely based on the monthly premium is the most expensive and common mistake, as it may not cover all medications adequately.

With changes to Medicare Part D plans in 2026, taking the time to organize and research plans during the open enrollment period is crucial. Creating a medication list, understanding tier costs, utilizing Medicare’s online tools, and checking pharmacy options are key steps in finding the right plan.

Beneficiaries should be aware of plan cancellations affecting 2026 coverage and how they can present opportunities to switch plans. Understanding coverage changes, utilizing formulary exceptions, and contacting local SHIP advisers can help beneficiaries navigate the complexities of Part D plans effectively.

Read more at Yahoo Finance: Expert reveals that 95% of beneficiaries are overspending on prescriptions