During which scenario might beneficiaries incur the highest potential costs in Medicare?

When beneficiaries enroll in Medicare outside of the designated open enrollment period, they may face significant costs and penalties. This is primarily because late enrollment in Medicare plans can result in delayed coverage start dates and late enrollment penalties. For example, if someone delays signing up for Medicare Part B after their initial eligibility period, they might incur a 10% increase in their premiums for each full 12-month period they were eligible but did not enroll.

Additionally, outside of the open enrollment period, beneficiaries may not have the opportunity to adjust their coverage to better fit their health needs, which could lead to higher out-of-pocket expenses if they require services or treatments not adequately covered by their existing plan. These financial implications can accumulate quickly, making this scenario one of the most costly situations for Medicare beneficiaries.