Medicare Advantage C-SNPs and I-SNPs come under increased scrutiny

In a proposed rule published on November 28, 2025 covering a broad range of matters related to the Medicare Advantage (Part C), Medicare Prescription Drug Benefit (Part D), and Medicare cost plan regulations, the Centers for Medicare & Medicaid Services (CMS) included a request for information (RFI) specifically focused on the proliferation of certain Medicare Advantage special needs plans (SNPs).

The Medicare Advantage program authorizes three types of SNPs that limit enrollment to special needs individuals and tailor benefits to that population: (1) dual eligible SNPs (D-SNPs) limit enrollment to individuals who are dually eligible for Medicare and Medicaid and are highly integrated with state Medicaid programs, including through contracts with state Medicaid agencies; (2) chronic condition SNPs (C-SNPs) limit enrollment to individuals with specific severe or disabling chronic conditions; and (3) institutional SNPs (I-SNPs) limit enrollment to individuals who qualify as institutionalized or institutionalized-equivalent. A Medicare beneficiary may qualify for more than one type of SNP. For example, a dually eligible beneficiary with qualifying chronic conditions may be eligible for a C-SNP and a D-SNP.

This alert discusses the publication of the RFI and its potential impact on future C-SNP and I-SNP offerings.

Why did CMS issue the RFI?

CMS observes significant growth in offerings of C-SNPs and the high percentage of dually eligible beneficiaries enrolled in both C-SNPs and I-SNPs. In the case of C-SNPs, they have grown from 207 in contract year 2021 to 385 in contract year 2025. Enrollment under those plans likewise grew from under 400,000 to over 1.1 million. Accelerated growth in enrollment occurred in contract years 2023 and 2024. As part of this growth, the number of dually eligible individuals enrolled in C-SNPs doubled from contract year 2021 to 2025, with the largest jump from 2024 to 2025. CMS specifically notes a trend of individuals covered by D-SNP “look-alikes” moving to C-SNPs following efforts by CMS to curtail those plans that had high dual eligible enrollment but were not certified as D-SNPs. By contrast, CMS found that enrollment in I-SNPs has remained “relatively consistent,” though CMS reports that dually eligible beneficiaries comprise roughly 90 percent of the total enrollment in I-SNPs each year.

The RFI situates these statistics within CMS’s longstanding efforts to reduce fragmentation between Medicare and Medicaid for dually eligible beneficiaries, including by encouraging enrollment in “integrated” D-SNPs that align with Medicaid coverage. The RFI specifically focuses on CMS’s prior efforts to curtail D-SNP “look-alikes” due to their lack of integration with Medicaid. While acknowledging the value of C-SNPs and I-SNPs for their target populations, CMS emphasizes that, unlike D-SNPs, neither is subject to state contracting requirements nor has the same scope of integrated care features of D-SNPs.

CMS signals concern that enrollment patterns in C-SNPs and I-SNPs may reflect an “intentional approach” by Medicare Advantage organizations to circumvent federal and state requirements for D-SNPs, including state authority to select which D-SNPs operate in their markets. The RFI invites stakeholder input on policy solutions for CMS’s future consideration.

What comments are solicited by CMS under the RFI?

The RFI solicits comments on the following topics:

• Whether CMS should establish a requirement for C-SNPs and I-SNPs to have a requirement to enter into state Medicaid agency contracts (SMAC) as under the D-SNP rules if a C-SNP or I-SNP would have a high concentration of dually eligible individuals.


• What methods CMS could consider to increase care coordination for dually eligible individuals enrolled in C-SNPs and I-SNPs.


• Whether CMS should apply D-SNP look-alike requirements to C-SNPs, including how such requirements may need to reflect the nature of C-SNPs and the impact of such requirements on individuals who could end up being left out of any SNP in their area.


• What other appropriate protections could be put into place to support high-quality, integrated care for dually eligible enrollees.


• Comments on policy ideas in the RFI to help inform potential future regulatory action.


• How to support improved access to treatment and care coordination for individuals with mental health conditions or substance use disorders, for which CMS believes SNPs could be situated to perform a critical role in supporting the improvement of care provided to individuals with serious mental illness.

What impact could the RFI have on future C-SNP and I-SNP offerings?

Stakeholder comments could materially shape the future design and availability of C-SNPs and I-SNPs. For example, if CMS were to apply requirements analogous to D-SNP rules, C-SNPs and I-SNPs meeting specified thresholds of dual eligible enrollment could be required to contract with state Medicaid agencies and to adopt more extensive integrated care features and significantly modified benefit structures. Such changes could create barriers to market entry if Medicaid agencies elect not to contract, shift plan focus away from beneficiaries’ chronic conditions or institutional care needs in favor of broader integration obligations, or otherwise affect the feasibility of C-SNP and I-SNP offerings.

At this time, CMS has not specified a comment deadline or indicated a timeline for any subsequent rulemaking based on this RFI.

For more information or if you have any questions, please contact the author.