Network Adequacy: Why Compliant Networks Still Fail Members

Key Takeaways

• Network adequacy is the set of regulatory standards that determines whether a health plan has enough contracted providers, in the right specialties and locations, for members to get care within a reasonable time and distance.
• Every network adequacy standard is calculated from the plan's own provider directory data, so an inaccurate directory makes a filing unreliable no matter how well the network is actually built.
• Keeping directory data accurate takes continuous checks against several independent sources, because a directory that relies on providers to report their own changes will miss the ones who don't.

A Medicare Advantage plan can pass every network adequacy test CMS runs and still leave a member calling doctor after doctor without getting an appointment. Peer-reviewed research found that 17.5% of the primary care physicians listed in an average Medicare Advantage network were not providing primary care to any Medicare patient.

Different regulators enforce network adequacy standards for travel time, provider counts, and appointment waits, but all of them are calculated from the same provider data the plan submits. So a plan can pass regulatory review even when members can't get an appointment. Regulators test the list the plan submits, and that list can include entries with inaccurate or outdated information, such as doctors who have moved or retired.

What is network adequacy?

Network adequacy is the set of regulatory standards that determines whether a health plan has enough contracted providers, in the right specialties and locations, for members to get care within a reasonable time and distance. The standards exist so that a member who needs a cardiologist or a primary care physician can reach one in the plan's network without an unreasonable drive or an unreasonable wait.

The concept is simple, but compliance is harder because there is no single federal standard that governs network adequacy across all plan types. Medicare Advantage, the ACA marketplaces, Medicaid managed care, and state-regulated commercial plans each set their own rules, and states can add requirements of their own. So a plan that sells several lines of business in several states answers to several definitions of adequate, all applied to the same network.

Network adequacy requirements: the three standards

Regulators judge a network on how far members have to travel, how many providers the plan has under contract, and how soon members can get an appointment. Each program uses a different mix of the three. Medicare Advantage spells them out most precisely in 42 CFR 422.116, so the details below come mostly from that program.

The reach of these standards shifted in 2026. Since January 1, 2026, state-based marketplaces have had to apply quantitative time and distance standards like the federal marketplace's. But the 2027 Payment Notice would have ended that requirement on July 20, 2026. A federal court stayed that change on July 16, 2026, so the requirement remains in place while the case continues.

Time and distance standards

A member in rural Montana can be expected to drive farther to a cardiologist than a member in Chicago, and CMS sets a different maximum for each. Every year CMS publishes maximum time and distance limits for each provider and facility specialty type, set separately for large metro, metro, micro, rural, and counties with extreme access considerations (CEAC). At least 90% of beneficiaries in large metro and metro counties, and at least 85% in micro, rural, and CEAC counties, must live within the limit for every specialty.

CMS measures each listed location against where beneficiaries live, so a wrong address puts an error into the filing at the very first step. CMS guidance even specifies that providers be listed where they see patients, not at a hospital where they only perform procedures.

Minimum provider counts

Plans must also contract with a minimum number of providers and facilities in each specialty type across the service area. A provider only counts toward that minimum if they are within the maximum time and distance of at least one beneficiary. The count and the travel check both use the same addresses. A cardiologist who retired last spring or moved out of the county still counts toward the minimum as long as the directory lists them at their old address.

Appointment wait time and access standards

Wait time standards come closest to testing real access, because they ask whether a member can actually get an appointment, not just whether a provider is within driving distance. They are also the least uniform of the three, appearing in marketplace and Medicaid managed care rules but not in Medicare Advantage.

On the federally facilitated marketplace, enrollees must be able to schedule a behavioral health appointment within 10 business days, a routine primary care appointment within 15 business days, and a non-urgent specialty appointment within 30 business days, at least 90% of the time. Plans show compliance through third-party secret shopper surveys, which currently cover primary care and behavioral health. Medicaid managed care rules cap state standards at the same 10 business days for outpatient mental health and substance use disorder care and 15 for primary care, with the same 90% bar. Those limits start with rating periods on or after July 9, 2027.

Medicare Advantage has no formal wait time standard, but members can still report access failures to CMS. An enrollee's network access complaint can prompt CMS to review a plan's network outside the normal three-year review cycle. Whether the test is travel distance or appointment availability, regulators work from provider data the plan supplies, so a wrong record means a wrong result.

Who sets network adequacy standards

Which rules apply depends on a plan's line of business. CMS sets the Medicare Advantage rules and certifies qualified health plans on the federally facilitated marketplace, while states that run their own exchanges review their own marketplace plans. State Medicaid agencies set standards for Medicaid managed care within federal minimums, and state departments of insurance regulate commercial plans. State standards can also be stricter than federal ones.

For Medicare Advantage, CMS measures 29 provider specialty types and 14 facility specialty types. Plans submit their networks in Health Service Delivery (HSD) tables, which CMS checks with an automated review. Each contract goes through a full network review every three years. CMS can also review a network off-cycle after a new or expanding service area application, a significant contract termination, an enrollee complaint, or a gap the plan discloses. So the burden is several overlapping frameworks, all computed from the same provider data.

Why adequate networks still fail members

Time and distance, provider counts, and wait times are all computed from the plan's own provider data, so a filing built on wrong data can pass regulatory review and still be wrong. Providers move, retire, stop taking new patients, or leave the network, and the old listing often stays in the directory.

A ghost network is a provider directory that lists doctors members can't actually get care from. A 2026 Johns Hopkins study in Health Services Research found that 17.5% of the primary care physicians listed in an average Medicare Advantage network were general ghosts, meaning they were not providing primary care to any Medicare patient. Another 11.5% were network-specific ghosts, meaning they saw Medicare patients in general but not that network's enrollees. Primary care ghosts can block more than primary care, because HMO and point-of-service plans usually require a primary care referral before they cover a specialist visit. A member who can't find a primary care doctor who is actually taking patients may not be able to reach a specialist either.

CMS has been clear that keeping this data right is the plan's responsibility. Its network adequacy guidance warns that the provider supply file CMS publishes may not reflect the providers available in real time, and it states that plans remain responsible for validating the data they use to populate their HSD tables.

Commercial plans have a directory rule too. The No Surprises Act requires group and individual plans to verify their provider directory information at least every 90 days, but a provider who moves the day after a check can stay listed at the old address for nearly three months. Medicare Advantage is getting its own 90-day rule. The REAL Health Providers Act, signed in February 2026, requires it starting in plan year 2028. In October 2026, CMS proposed the detailed rules for how plans must comply. Those rules are not final yet.

What accurate provider data actually requires

To file from a directory with confidence, a plan needs continuous verification instead of a periodic refresh. That verification has to draw on several independent data sources instead of provider attestation alone, and it has to confirm whether a provider is taking appointments, not just whether the address and phone number are right.

Attestation, where providers confirm their own listings, falls short because it depends on the provider answering. The offices least likely to respond to a plan's outreach are often the ones with the most outdated listings, such as a practice that closed, a physician who retired, or a group that moved and never updated its roster. The table below is Garner’s recommended approach, not a regulatory standard. Federal rules set a 90-day check on directory information overall, but not a schedule for each field.

Garner built its own provider data on this model. Starting from claims data that covers 75% of U.S. medical claims, Garner checks daily for signals such as a provider billing from a new ZIP code or no longer billing new-patient visits, and uses them to keep phone, address, and appointment availability current. Garner also runs automated checks of booking and website availability. A call center phones offices directly. Together, the claims signals, automated checks, and calls reach 92% accuracy across phone, address, and appointment availability.

Verify the directory before you file

You can't know whether your network is adequate if you can't trust the directory behind the measurements. The HSD table submission, the three-year network review, each exception request, and a member's search for a doctor all start from the same provider records. So accurate provider data has to come before any filing, because every filing is calculated from those records.

Book a demo to compare your provider data against a continuously verified baseline before your next HSD submission.

FAQs

What is network adequacy?

Network adequacy is the set of regulatory standards that determines whether a health plan has enough contracted providers, in the right specialties and locations, for members to get care within a reasonable time and distance. The standards differ by line of business and by state, so Medicare Advantage, marketplace, Medicaid managed care, and commercial plans each answer to their own rules.

What are the network adequacy requirements for 2026?

In 2026, Medicare Advantage plans must meet CMS time and distance and minimum provider count standards, with 85–90% of beneficiaries within the limits depending on county type. Plans on the federally facilitated marketplace must also meet appointment wait times of 10 business days for behavioral health, 15 for routine primary care, and 30 for non-urgent specialty care, at least 90% of the time. State-based marketplaces still have to apply quantitative time and distance standards for now. CMS tried to remove that requirement in a 2027 rule, but a federal court stayed the change in July 2026.

How is network adequacy measured?

Network adequacy is measured by comparing a plan's provider data against where its members live. Regulators test travel time and distance from provider addresses, count contracted providers in each specialty and county type, and use secret shopper calls to test appointment wait times in marketplace and Medicaid plans.

What is a ghost network?

A ghost network is a provider directory that lists doctors members cannot actually get care from, because the doctors moved, retired, stopped seeing new patients, or do not see the plan's members. Research found that 17.5% of listed primary care physicians in an average Medicare Advantage network were not providing primary care to any Medicare patient.

Does telehealth count toward network adequacy standards?

Telehealth counts toward Medicare Advantage network adequacy only in a limited way. A plan earns a 10-percentage-point credit toward the share of beneficiaries who must live within time and distance limits when it contracts with telehealth providers in specialties such as primary care, cardiology, and psychiatry. Marketplace, Medicaid, and commercial plans follow their own telehealth rules.