The 2025 call letter landed with the usual wave of takes — here is what it actually said about network adequacy and what your plan needs to do about it.
Cut Through the Noise
Every year the CMS Medicare Advantage and Part D Annual Call Letter drops, and within 48 hours the industry trade publications fill up with the same breathless recap: enrollment changes, benchmark rates, star ratings. Network adequacy gets half a paragraph at the bottom. That is a mistake. For plans in active network builds — or plans that should be — the network adequacy provisions are the ones with the sharpest operational teeth. Here is what the 2025 letter actually said, and what each piece means if you are building or managing a network right now.
Time-Distance Standards: The Baseline Holds, But the Scrutiny Doesn't
CMS did not restructure the core time-distance standards in the 2025 call letter. Urban plans still face the 15-minute/5-mile thresholds for primary care; rural plans still operate under the 60-minute/60-mile standards. What changed is how CMS signals it intends to enforce them.
The letter included explicit language around enhanced monitoring for outlier counties — counties where plans have historically submitted adequacy certifications that CMS considers borderline. The implication for network build leaders is clear: filing at the minimum is no longer safe. If your plan is at 15 minutes and 4.9 miles in a county, you are on a list somewhere. Plans that want regulatory breathing room need to build to a buffer, not to the floor.
Operationally, this means your gap analysis tools need to model at threshold plus margin, not threshold only. If you are running calculations in a spreadsheet, that nuance is almost certainly getting lost.
Specialty Requirements: Behavioral Health Gets Sharper
The 2025 letter continues the multi-year trend of tightening specialty network requirements for behavioral health — specifically outpatient mental health and substance use disorder treatment. CMS is not simply reiterating that behavioral health matters; it is pushing plans toward demonstrable access, which means shorter appointment wait time compliance and clearer documentation that listed providers are actually accepting new patients.
For network build leaders, this creates a specific credentialing and directory problem. Behavioral health providers have some of the highest panel-closure and practice-change rates in any specialty. A provider who attested to accepting new patients in March may have closed their panel by June. Adequacy submissions that rely on stale attestations in behavioral health are a material compliance risk.
The fix is not just more outreach — it is a more frequent re-attestation cycle for behavioral health specifically, and a directory monitoring process that flags changes between submission windows.
Good Faith Effort Standard: Documentation Is Now the Product
CMS has historically accepted good faith effort exceptions for counties where a plan cannot meet time-distance standards because an insufficient number of providers exist in a market. What the 2025 letter makes clearer is that good faith effort is not a narrative — it is a record.
Plans seeking exceptions will face closer review of their outreach documentation: who was contacted, when, through what channel, and what the response was. A log that says "called, no answer" three times is not going to hold up. CMS wants to see a structured, multi-touch outreach record that demonstrates genuine, repeated attempts to contract with every available provider in the specialty and geography.
This is not a new concept, but the 2025 letter sharpens it. If your outreach tracking lives in a shared spreadsheet with a column called "Notes," you are not prepared for a good faith effort review.
Provider Directory Requirements: Real-Time Is the New Standard
The call letter reaffirms CMS's expectation that provider directories be updated within 30 days of a provider change — and signals continued enforcement attention on directories that fall short. More practically, CMS is increasingly treating directory accuracy as a proxy for network integrity. A directory with stale or inaccurate data is not just a consumer protection problem; it is a signal that the underlying network may not actually exist as attested.
For plans with large networks across many counties, this is an operational burden that requires a real system — not periodic manual audits. Every provider termination, address change, or panel status change needs to trigger a directory update workflow, not land in a ticket queue that gets resolved when someone has time.
What to Do Now
- Audit your time-distance calculations with a buffer built in. If you are relying on threshold-only compliance in any county, understand that your risk profile just increased.
- Build a behavioral health re-attestation cycle. Do not rely on annual attestations for a specialty with this rate of panel change. Quarterly touch-points for behavioral health providers are the new minimum.
- Upgrade your outreach logging. Every provider contact — call, fax, portal message, in-person — needs a structured, timestamped record. "Tried to call" is not an audit-ready log.
- Treat your provider directory as a live system, not a submission artifact. The 30-day update standard requires a workflow, not a reminder on someone's calendar.
The 2025 call letter did not reinvent network adequacy. It sharpened CMS's posture on evidence and documentation. Plans that are building networks on informal systems — spreadsheets, shared folders, email threads — are the ones most exposed to what comes next.