How CMS Scores Medicare Advantage Network Adequacy: The Two Tests

The short answer: two tests, run county by county

CMS scores a Medicare Advantage network with two tests under 42 CFR 422.116, run separately for every county and every provider or facility type in the service area. The first is a minimum count: enough contracted providers (or, for acute inpatient hospitals, beds) for the size of the county. The second is time and distance: at least 90% of beneficiaries in Large Metro and Metro counties, and at least 85% in Micro, Rural and CEAC counties, must have one provider of that type within the published maximum minutes and miles. You need both.

Everyone in this business can recite "90% and 422.116." Far fewer people can explain why a network with a dozen cardiologists on the HSD table still fails cardiology in a county. That gap is where builds die. Usually in the deficiency round, usually against a date that doesn't move.

So here are the mechanics, in the order CMS applies them. County designation first, because it sets every other number. Then the count. Then time and distance. Then the credits and customizations that bend the rules, and the review cycle that decides when anyone at CMS actually looks.

Step one: the county designation sets every number

Each county gets one of five designations, based on its population and its density in persons per square mile. The designation picks your percentage threshold, the ratios behind your minimum counts and the time and distance maximums. Get it wrong in your planning model and every number downstream is wrong with it.

Designation	Qualifies when (population, density)	Must have access	Counties in 2026 file
Large Metro	1,000,000 or more at density 1,000+; or 500,000 to 999,999 at density 1,500+; or any population at density 5,000+	90%	84
Metro	1,000,000+ at density 10 to 999.9; 500,000 to 999,999 at 10 to 1,499.9; 200,000 to 499,999 at 10 to 4,999.9; 50,000 to 199,999 at 100 to 4,999.9; 10,000 to 49,999 at 1,000 to 4,999.9	90%	763
Micro	50,000 to 199,999 at density 10 to 99.9; 10,000 to 49,999 at 50 to 999.9	85%	763
Rural	10,000 to 49,999 at density 10 to 49.9; under 10,000 at 50 to 999.9	85%	1,074
CEAC (Counties with Extreme Access Considerations)	Any population at density under 10	85%	578

Designations move. Between the 2025 and 2026 HSD Reference Files, CMS listed 6,862 county and specialty criteria changes, and 807 of them came from counties changing designation. Pull the current HSD Reference File every year. Last year's crosswalk is a guess.

One small change worth knowing: since the CY2026 rule, "county" in 422.116 expressly includes Census Bureau county equivalents. CMS called it longstanding policy. It still matters if your service area touches a state that doesn't use counties.

Where the 85% comes from, and why it matters less than people think

Section 422.116(d)(4) sets the percentage. Micro, Rural and CEAC counties need 85% of beneficiaries within the standard; Large Metro and Metro counties need 90%. Non-urban counties used to be held to 90% too. The CY2021 final rule lowered them to 85%.

Five points sounds like relief. In practice it rarely decides a rural county. What decides it is geography: where the members live relative to the few places a specialist will practice. A CEAC county with one town and members spread across a hundred miles of highway fails at 85% just as surely as it would at 90%, because the problem isn't the last five percent. It's the thirty percent who live past the one clinic. We'd spend less time on the threshold and more on the map.

The minimum count, worked for Baldwin County, Alabama

The count test has its own formula, set out in 422.116(e). It looks harder than it is.

First, CMS works out how many beneficiaries you are expected to cover. That figure is the county's total Medicare beneficiaries multiplied by a "95th percentile base population ratio," which CMS recalculates every year for each county type. The ratio is the MA penetration of the contract sitting at the 95th percentile, meaning 95 percent of plans have lower enrollment. For 2026 the ratios are 0.07687 for Large Metro, 0.10585 for Metro, 0.12119 for Micro, 0.11297 for Rural and 0.14328 for CEAC. Then each provider type has a minimum ratio per 1,000 beneficiaries. Multiply, divide by 1,000, and round up to the next whole number. The regulation says CMS "rounds it up," and it means it.

Baldwin County, Alabama (SSA code 01010) is a Metro county with 64,923 Medicare beneficiaries in the 2026 file. At the Metro ratio of 0.10585, CMS lists 6,873 beneficiaries required to cover. Here is what that produces:

Type	Minimum ratio per 1,000	Ratio × 6.873	Minimum required
Primary Care (S03)	1.67	11.48	12
Cardiology	0.27	1.86	2
Psychiatry	0.14	0.96	1
Clinical Psychology	0.15	1.03	2
Clinical Social Work	0.25	1.72	2
Acute Inpatient Hospital (beds)	12.2	83.9	84 beds
Outpatient Behavioral Health	Fixed	n/a	1

Look at clinical psychology. 1.03 becomes 2.

Every figure above matches CMS's own file for Baldwin. The facility types other than acute inpatient, Outpatient Behavioral Health included, carry a flat minimum of one. Two conditions sit underneath all of it. A provider counts toward the minimum only if they are within time and distance of at least one beneficiary in CMS's sample, and only if they are not telehealth-only. For primary care, CMS sums six specialty codes (001 General Practice through 006 Nurse Practitioners) and scores them as one group under S03.

The time and distance table most builds are really fighting

The base maximums live in Table 1 of 422.116(d)(2) and repeat in the HSD Reference File. A few rows that come up on almost every build, shown as maximum minutes / maximum miles:

Type	Large Metro	Metro	Micro	Rural	CEAC
Primary Care	10 / 5	15 / 10	30 / 20	40 / 30	70 / 60
Cardiology	20 / 10	30 / 20	50 / 35	75 / 60	95 / 85
Psychiatry	20 / 10	45 / 30	60 / 45	75 / 60	110 / 100
Clinical Social Work	20 / 10	30 / 20	50 / 35	75 / 60	125 / 110
Outpatient Behavioral Health	20 / 10	40 / 25	55 / 40	60 / 50	110 / 100

Baldwin carries the base Metro values for these rows in 2026: primary care at 15 minutes and 10 miles, cardiology at 30 and 20. One oddity to leave alone. For several facility types the Rural maximum is lower than the Micro one (acute inpatient is 80 minutes and 60 miles in Micro, 75 and 60 in Rural). That is what the published table says. Don't "fix" it in your model.

Why you can pass the count and fail the distance

This is the question plans have been putting to CMS for years, and CMS answered it plainly in its 2017 criteria guidance. The two checks start from opposite ends. The count check starts from your provider addresses and asks whether at least one sample beneficiary is in range. The time and distance check starts from every sample beneficiary and asks whether enough of them have a provider in range.

CMS's own illustration: five specialists in one building, one beneficiary living across the street. All five count toward the minimum. None of them helps the member forty miles east.

So a network recruited to the count, which is how most recruiting targets get written, clusters in the county seat and fails the members at the edges. Recruit to geography instead. The question for every open slot is not "how many more cardiologists do we need" but "which members are still outside 20 miles, and who practices nearest to them."

Two things make this harder to predict from inside the plan. The beneficiary side of the test comes from the MA Medicare Sample Census, which CMS says is representative for each county and "is only available to CMS." You can't see where CMS's members are. And the test ignores lines on the map: the criteria are not restricted by state or county boundaries, so a provider just over the border can serve your county.

Then there's distance itself. Here is what CMS actually publishes. The regulation says the metrics "measure the relationship between the approximate locations of beneficiaries and the locations of the network providers." CMS measures both travel time and travel distance from representative beneficiary locations, and its published methodology derives time from distance using area-specific speed assumptions. A 2010 HPMS memo described distance as a formula-based estimate of driving distance between coordinates, with time set by speed (30 mph urban, 45 suburban, 55 rural). No current public CMS document says whether today's Network Management Module routes on roads or measures a straight line. Anyone who tells you with certainty is guessing. Treat your own distances as estimates, and let CMS's engine be the referee. We cover how to do that in why your network passes internally and fails CMS.

Credits and customization: what bends, and what doesn't

Three credits can each add 10 percentage points to your measured percentage for a county and specialty.

• Telehealth, (d)(5). When the network includes telehealth providers furnishing additional telehealth benefits in listed specialties: Dermatology, Psychiatry, Cardiology, Neurology, Otolaryngology, Ophthalmology, Allergy and Immunology, Nephrology, Primary Care, Gynecology/OB-GYN, Endocrinology, Infectious Diseases, Clinical Psychology, Clinical Social Work and Outpatient Behavioral Health.
• Certificate of Need, (d)(6). For affected types in states with CON laws or similar restrictions. CMS's December 2024 guidance adds that the credit "will not be applied" where the county's standards are customized.
• New or expanding service area, (d)(7). For applicants, at the time of application and for the duration of the review. It ends when the contract year starts.

None of them touches the minimum count. The credits apply to the percentage of beneficiaries within the standard, and telehealth-only providers never count toward the minimum. A telehealth vendor can lift your psychiatry percentage in a rural county. It cannot fill your psychiatry count there.

Customization is the other lever, and it only goes one way. Under (d)(3), when utilization or supply patterns call for it, CMS maps provider supply against its sample census, finds the distance at which 90% of the population has at least one provider, rounds up to the next multiple of 5 and converts that to time with a county-type multiplier. CMS's own example: 51.2 miles becomes 55. Customized standards can only be higher than the base, never lower. In the 2026 file, 4,549 of the changes from 2025 were customizations; Elmore County, Alabama primary care moved from 10 miles and 15 minutes to 15 miles and 25 minutes.

Don't plan around a customization, though. The same year, 1,506 changes were returns to base criteria. When a standard won't bend and supply really isn't there, the route is an exception request, which we walk through in CMS network adequacy exception requests.

When CMS actually looks: the triennial review and its triggers

Under the December 2024 network adequacy guidance, CMS reviews contract networks on a triennial basis. Contracts due for review are prompted to upload their full HSD tables into the Network Management Module in mid-June, for the current contract year. Applicants upload as part of the application, for the upcoming year. Before the formal review, CMS offers an informal "Consultation" upload with technical assistance. Take it.

Four events can pull a review forward: an application (initial or service area expansion), a termination CMS considers significant, a network access complaint, and a gap the plan discloses itself, which plans must report to their CMS Account Manager. A triggered full review may reset the triennial clock. Applicants that used letters of intent go through the triennial review in their first operational year, no matter where they were in the cycle. The consequences are spelled out: CMS may deny an application, and operating contracts that fail may face compliance or enforcement actions. If you are expanding, the calendar matters as much as the math; see the service area expansion timeline.

Any organization with a contract ID can also upload to NMM at any time to test itself. Most don't do it often enough.

The count is arithmetic. You can finish it in a spreadsheet in an afternoon, and most plans do. The distance test is geography measured against members you cannot see, and it is the one that sends builds into the deficiency round. Spend your recruiting weeks on the people outside the circle, not on the next name inside it.

That is how Blueprint's adequacy engine is set up: it scores against the standards you load, on the same records your recruiters work, and shows which members sit outside the standard. Distance is straight-line today, so it labels a pass "unconfirmed" until it's measured on roads. You can try it on sample data on the network map.