The D-SNP Network Adequacy Handbook

Why D-SNP Networks Are Not Standard MA Networks

Plans that build their first Dual Eligible Special Needs Plan network by extending their existing Medicare Advantage network build playbook encounter a specific class of compliance problems — problems that are entirely avoidable but not visible until you understand that D-SNP network adequacy operates under a distinct regulatory framework with requirements that do not exist in standard MA.

The core difference is structural. Standard MA networks must satisfy CMS HSD requirements. D-SNP networks must satisfy CMS HSD requirements and align with the state Medicaid network standards in each state where the plan operates, and meet the requirements established in the state's Memorandum of Understanding with the plan, and demonstrate coordination of care capacity that reflects the clinical complexity of the dually eligible population the plan serves. That is four distinct regulatory requirements where a standard MA plan has one.

Plans that treat D-SNP adequacy as a checkbox variation on MA adequacy will miss the Medicaid alignment requirements, underinvest in coordination agreement infrastructure, and arrive at their HPMS filing cycle with gaps that the standard MA process never would have surfaced. The regulatory scrutiny for D-SNP filings has increased substantially since the SUPPORT Act provisions and subsequent 2023 integrated care regulations took effect. CMS reviews D-SNP networks with specific attention to whether the plan can actually serve the integrated care needs of dually eligible beneficiaries — not just whether it has enough providers in enough counties.

Understanding the MOU Requirement

Every D-SNP must execute a Memorandum of Understanding with the state Medicaid agency in each state where it operates. The MOU is not a formality — it is a binding agreement that specifies the coordination obligations between the D-SNP and the state Medicaid program, and it creates network requirements that go beyond what HPMS filing instructions specify.

CMS's regulations at 42 CFR 422.107 establish the minimum requirements for D-SNP MOUs. The MOU must describe how the D-SNP will coordinate the full scope of Medicare and Medicaid benefits for dually eligible enrollees, which requires the D-SNP to demonstrate that its provider network can support that coordination in practice. A D-SNP that contracts with Medicare Advantage-focused primary care providers but does not ensure those providers have the Medicaid enrollment and behavioral health coordination capacity to serve dual eligibles is technically meeting an HSD standard while failing its MOU obligations.

MOU terms vary significantly by state. Some states have detailed network requirements built directly into their MOU templates — specific provider types, specific coordination protocols, specific access requirements for behavioral health and long-term services and supports (LTSS) that are not part of standard CMS HSD requirements. Plans entering a new state with a D-SNP must obtain and review the state's MOU template before building the network, not after. The MOU requirements in some states are extensive enough that they add weeks to the county selection and provider outreach timeline when they are discovered late.

MOU execution itself requires lead time. States have their own review and execution processes for D-SNP MOUs, and those processes do not run on HPMS filing calendar logic. A plan that finalizes its D-SNP market entry decision in August and expects to execute a state MOU by October is likely operating on an unrealistic timeline. State Medicaid agencies are not structured to expedite MOU execution for new entrants. Build MOU execution into the D-SNP network timeline with the same lead time discipline as credentialing — and add buffer, because the state agency controls the pace.

Dual Adequacy Standards: Meeting Both CMS and State Requirements

D-SNPs face what is effectively a dual adequacy standard: the CMS HSD requirements that govern all MA networks, and the state Medicaid network adequacy standards that apply to managed care plans covering the state's Medicaid population. For dually eligible beneficiaries, the plan must demonstrate access to both Medicare-covered and Medicaid-covered services, and the standards governing each are set by different authorities with different methodologies.

CMS's approach to D-SNP adequacy has evolved toward greater integration. The 2023 integrated care regulations established requirements for D-SNPs to demonstrate coordination between Medicare and Medicaid covered services, which means that a network that satisfies CMS HSD requirements in isolation is not sufficient if it cannot demonstrate the care coordination capacity that integrated care requires. CMS looks specifically at behavioral health access, LTSS provider availability, and care management capacity when reviewing D-SNP filings. These are not categories in the standard HSD table — they are evaluated through the integrated care attestations and coordination documentation that D-SNPs must submit alongside their HPMS filing.

State Medicaid adequacy standards for the same counties where the D-SNP operates may use entirely different time-distance thresholds, different specialty categories, and different measurement methodologies than CMS HSD. Plans must map both standards simultaneously for every county in the D-SNP service area. Building a network that satisfies CMS but not the state creates a compliance gap with the state Medicaid agency. Building a network that satisfies the state but not CMS creates an HPMS deficiency. The plan must do both, and the more restrictive standard in each county-specialty combination is the binding constraint.

For D-SNP network build, the minimum standard in any county for any specialty is the more restrictive of the CMS requirement and the state Medicaid requirement. Building to only one is building to the wrong target half the time.

In practice, this means building a dual-standard compliance matrix for each state before outreach begins. The matrix should display, for each required specialty in each county, the CMS HSD threshold and the state Medicaid threshold, with the binding constraint identified. The outreach team works from the binding constraint column. This is more complex to build than a standard HSD gap map, but it is the only way to avoid discovering compliance gaps late in the build cycle when the state Medicaid agency flags the D-SNP for inadequate access under state standards.

What CMS Looks For in D-SNP Adequacy Filings

CMS's review of D-SNP network filings has become more substantive over the past three years. Plans that previously filed adequate HSD tables and standard exception documentation are finding that CMS is asking more specific questions about the D-SNP's ability to serve the integrated care needs of dually eligible beneficiaries.

Specific areas of elevated scrutiny include behavioral health access — given the high prevalence of behavioral health conditions in the dual eligible population, CMS pays particular attention to whether the D-SNP has adequate in-network behavioral health access, including substance use disorder treatment providers — and LTSS coordination capacity. D-SNPs that lack in-network LTSS providers or care managers with LTSS coordination experience are flagged for follow-up. Plans that have served the traditional MA population but not the Medicaid population may have networks with significant LTSS gaps that were not visible in prior standard MA filings.

Care management documentation is increasingly part of D-SNP adequacy review. CMS expects D-SNPs to demonstrate that they have care management capacity scaled to the needs of their dually eligible population — not as an abstract attestation, but as a documented capability backed by contracted or employed care managers with the appropriate expertise. A D-SNP with 5,000 dually eligible enrollees and care management capacity designed for 2,000 is not meeting the integration standard the regulations envision, and CMS is increasingly capable of identifying that gap.

The compliance posture that positions D-SNP plans well for CMS review has three elements: a network that meets both the CMS HSD and state Medicaid adequacy standards for every required specialty; MOU compliance documentation that demonstrates active coordination with the state Medicaid agency rather than a paper agreement; and care management capacity documentation that is proportionate to the enrolled population and demonstrates actual integration of Medicare and Medicaid covered services. Plans that can demonstrate all three are well-positioned for the level of scrutiny D-SNP filings currently receive.