Enrollment in Medicare Advantage (MA) has climbed steadily over the past decade, and of late a key area of focus in this market has been around special needs plans, or SNPs.
A new report from KFF finds that these SNPs now account for 21% of all MA enrollees, up from 13% in 2018, the year they became a permanent part of the MA program. Enrollment in SNPs has grown from 2.6 million to 7.3 million in that time frame.
That makes SNPs a major driver in MA growth, according to the study, making for 48% of the total enrollment gains between 2024 and 2025.
There are three types of SNPs based on a specific population, all of which are highly vulnerable patient groups. Their overall expansion has been driven in large part by dual SNPs, which are available to individuals enrolled in both Medicare and Medicaid.
KFF found that enrollment in D-SNPs increased from 2.2 million people in 2018 to 5.5 million in 2024, accounting for more than 90% of the growth among SNPs.
However, sign-ups for chronic condition SNPs, or C-SNPs, are gaining steam. The study found that these plans accounted for 75% of overall SNP enrollment growth between 2024 and 2025, adding 476,300 new members and far outpacing the 159,400 new enrollees in D-SNP plans.
The third category, institutional special needs plans, are for people who need to be in long-term care facilities, though many of these individuals are also dually eligible.
The survey said the changing dynamics in the SNP space reflect evolving regulations on each of the different categories.
"The acceleration of C-SNP enrollment growth and slowing of D-SNP enrollment growth coincided with implementation of new rules for D-SNPs requiring greater integration between Medicare and Medicaid," the researchers wrote. "C-SNPs are not required to have a similar level of integration."
As enrollment in SNPs rises, it's also highly concentrated among certain for-profit insurance carriers. Just 14% of people in SNPs were covered by a nonprofit health plan.
UnitedHealthcare and Humana collectively account for 54% of total SNP enrollment, and UnitedHealth specifically accounts for half of people in C-SNPs. Given that UHC is the largest individual insurer in the MA market overall, it follows that it also has the largest share of D-SNP members (38%) and I-SNP members (51%).
That said, the SNP space is more concentrated than the broader MA space, where UHC accounts for 29% of enrollment.
"Across all three SNP types, which enroll some of the most vulnerable beneficiaries in the Medicare population, a few large national carriers account for larger shares of enrollment in the SNP market as compared with the overall Medicare Advantage market," the researchers said.