Part B Givebacks Drive Medicare Advantage Enrollment Surge—But Whether Care is Accessible After Enrollment Remains Unclear
Medicare Advantage plans that introduced a Part B premium giveback saw a 33.3% increase in enrollment compared to those that did not
In a rapidly shifting Medicare Advantage (MA) landscape, new research sheds light on a compelling but understudied benefit: the Part B premium giveback. A published June 6 in JAMA Forum found that Medicare Advantage plans offering Part B premium givebacks—rebates that offset some or all of the at least $174.70 monthly Part B premium—experienced a 33.3% increase in enrollment compared to plans without the benefit, based on an analysis of more than 130 million enrollee-years of data.
The study found that this growth comes amid a dramatic rise in the prevalence of givebacks, increasing from just 4.3% of MA plans in 2018 to nearly 19% by 2024. In real numbers, that means 3.4 million enrollees in 2024 received an average monthly rebate of $77, totaling approximately $261 million in Medicare expenditures every month.
“These findings highlight that the Part B giveback is highly salient to beneficiaries,” said Mark Meiselbach, PhD ’22, assistant professor in Health Policy and Management and the study’s lead author. “In an increasingly competitive MA marketplace, even modest givebacks appear to drive enrollment.”
The study employed a difference-in-differences design, comparing enrollment patterns across 18,627 MA plan-years between 2018 and 2024. Researchers controlled for key plan characteristics, such as star ratings, premiums, and benefit design. The results reveal a dose-response relationship: the greater the giveback, the higher the enrollment bump. For example, plans offering rebates that covered more than 80% of the standard Part B premium saw enrollment increases of up to 245%.
However, the study also raises important questions about trade-offs. Plans offering givebacks tended to have higher out-of-pocket maximums and Part D deductibles and served populations with lower risk scores, indicating that potentially healthier members with fewer expected medical needs enrolled in the giveback plans.
“While these rebates put real money back in enrollees’ pockets, they may come at the expense of other types of coverage or access,” Meiselbach said. “We don’t yet know whether these benefits ultimately help or harm members’ long-term health outcomes, especially for those who might face higher cost-sharing if they become sick.”
MA plans are funded through a system in which private insurers bid against benchmarks set by the Centers for Medicare & Medicaid Services (CMS). When plans bid below those benchmarks, the difference is returned as a rebate, which can be used for benefits like vision and dental—or, increasingly, Part B premium rebates. These givebacks are especially appealing because they reduce a mandatory monthly expense for beneficiaries, which is often deducted directly from their Social Security checks.
Historically, Part B givebacks were a niche offering. In the past, they were difficult to locate on official Medicare resources and less understood by consumers. However, with a growing reliance on brokers and third-party marketers—and a saturated market of plans touting similar perks, such as $0 premiums and dental coverage—givebacks may be emerging as a way to stand out.
Geographic variation also played a role. The study found that counties in states like Florida and Pennsylvania had some of the highest shares of MA enrollment in plans with givebacks. These are often areas with higher MA competition and a greater number of plan options overall.
Still, researchers emphasized that the long-term implications of this trend are not fully known. While givebacks represent a meaningful cash benefit, they may steer lower-income enrollees toward plans that are more financially risky in the event of serious illness. With MA plans increasingly competing on flashy benefits, the risk is that beneficiaries may choose plans based on immediate monetary savings rather than comprehensive, cost-effective care.
“Part B givebacks are a financial lever with strong enrollment appeal,” said Andrew Anderson, PhD, MHA, assistant professor in Health Policy and Management and the study's co-author. “But policymakers and consumers alike should be asking: at what cost? These are not just marketing perks—they shape access, affordability, and health care utilization.”
As Medicare Advantage continues to grow—now covering more than half of all Medicare beneficiaries—understanding the real-world impact of plan design choices is increasingly urgent. The study concludes by calling for further research into how trade-offs between supplemental benefits, rebates, and cost-sharing affect outcomes such as access to care, satisfaction, and overall health.
In the meantime, the authors urge both CMS and consumer advocates to ensure that seniors are fully informed about the potential costs and benefits of plans offering Part B givebacks. As more MA dollars are funneled toward visible rebates, transparency and health equity must remain at the forefront.
“We know this benefit influences plan choice,” said Meiselbach. “Now we need to understand how enrollees fare once enrolled in these plans.”
This research was supported by funding from Arnold Ventures.
