Growth has moved off the annual enrolment period and into the year: January lost 200,688 members, the months since added 973,859.UnitedHealth shed 887,444 lives at the plan-year turn and Humana took on 1,004,716. The file records 35,969,226 Medicare Advantage lives across 166 parent organisations.
Enrolment through September 2026·CMS source file·Next file (October 2026) expected 4 November
Lives · September 2026
35,969,226
166 parent organisations
Month on month
+28,395
+0.08% against the prior month
Year to date
+973,859
+2.78% since the plan year opened
Annual enrolment net
-200,688
-0.57% Dec → Jan
The board
12 parent organisations, 78.5% of Medicare Advantage lives.
Gap is year-to-date growth minus the market's, in points. Mix is the product split.
Select any row to drill into its county and product detail below.
Parent organisation
Sep 2026
Share
AEP net
YTD net
YTD %
Gap
YTD
Mix
Trend
UNH UnitedHealth
9,343,856
25.98%
-887,444
-63,059
-0.67%
-3.45
HUM Humana
7,192,294
20.00%
+1,004,716
+360,611
+5.28%
+2.50
CVS CVS Health / Aetna
4,224,749
11.75%
-119,892
+117,925
+2.87%
+0.09
KP Kaiser Permanente
2,072,846
5.76%
+602
+78,644
+3.94%
+1.16
ELV Elevance
1,900,857
5.28%
-308,358
-25,889
-1.34%
-4.13
CNC Centene
918,516
2.55%
+206
-46,425
-4.81%
-7.59
HCSC HCSC
897,233
2.49%
-97,612
+33,698
+3.90%
+1.12
Devoted Devoted Health
532,675
1.48%
+232,835
+88,618
+19.96%
+17.17
SCAN SCAN Health Plan
461,491
1.28%
+98,605
+47,265
+11.41%
+8.63
ALHC Alignment Healthcare
298,618
0.83%
+30,860
+33,009
+12.43%
+9.64
MOH Molina
222,594
0.62%
+15,025
-12,554
-5.34%
-8.12
CLOV Clover Health
158,437
0.44%
+34,746
+10,578
+7.15%
+4.37
— Market total
35,969,226
100%
-200,688
+973,859
+2.78%
—
HMOPPOSNPGroupProduct mix — individual HMO and PPO shown separately from SNP and employer group
From December 2025 to January 2026, UnitedHealth's Medicare Advantage enrolment fell by a net 887,444 and Humana's rose by 1,004,716; the other four of the six largest changed by 308,358 or fewer
All Medicare Advantage, by parent organisation: the six largest by September 2026 enrolment, each showing its change in members since January 2025, on one scale for all six panels. The black line is the organisation; grey lines are the other five. The December-to-January step is blue for a net gain and amber for a net loss, and each panel's label gives the change with its direction. Hover a month for its count.
Payer strategy — product and county
The plan file says how many. The contract/plan/state/county file says which
product and where, and that is where strategy is legible. Below is each carrier's
September 2026 product mix, its movement since August 2026, and the
shape of its county footprint. Book reassignments are removed from every movement figure; levels are
the book as filed.
UNHUnitedHealth+5,255
HMO +5,367PPO -3,007SNP +4,645Group -1,745
2,915 counties · grew in 1,558 · shrank in 1,110 · entered 1 · left 4 · top-10 counties = 8% of gains
national footprint · contracting · shedding PPO · adding HMO
HUMHumana-10,410
HMO -5,031PPO -1,871SNP -2,684Group -608
2,682 counties · grew in 949 · shrank in 1,465 · entered 2 · left 1 · top-10 counties = 16% of gains
national footprint · growing above market · shedding HMO
CVSCVS Health / Aetna+6,231
HMO +154PPO +3,878SNP +1,533Group +666
2,542 counties · grew in 1,138 · shrank in 974 · entered 5 · left 7 · top-10 counties = 17% of gains
national footprint · growing with market · adding PPO
KPKaiser Permanente+3,035
HMO +1,604PPO +10SNP +401Group +1,020
146 counties · grew in 85 · shrank in 46 · entered 2 · left 1 · top-10 counties = 69% of gains
The counties with the most genuine carrier movement between
August 2026 and September 2026, by total absolute change across all
parent organisations. Net is the county's own growth; churn is how much moved
regardless of direction — a county can be flat and still be a fight.
County
MA lives
Net
Churn
Biggest gain
Biggest loss
Los Angeles, CA
977,434
+1,263
4,653
SCAN Health Plan +744
Molina -420
Miami-Dade, FL
394,733
-420
4,264
Athena Healthcare Holdings, LLC +1,126
Centene -967
Riverside, CA
286,516
+403
1,971
Imperial Health Plan of California +293
UnitedHealth -226
Queens, NY
256,692
-276
1,856
Visiting Nurse Service of New York +431
Centene -477
Harris, TX
408,727
+258
1,750
HCSC +290
Centene -442
Maricopa, AZ
421,625
+29
1,697
SCAN Health Plan +358
Blue Cross Blue Shield of Arizona -319
Orange, CA
339,530
+650
1,590
SCAN Health Plan +319
UnitedHealth -130
Clark, NV
243,300
+91
1,407
Alignment Healthcare +538
UnitedHealth -319
San Diego, CA
332,158
+597
1,341
Astiva Health Holdings Incorporated +244
Molina -123
Kings, NY
237,380
-226
1,296
Visiting Nurse Service of New York +335
UnitedHealth -340
What this page is
Every Medicare Advantage member CMS records, every month — who holds them, which product they
sit in, and which county they live in. Figures are Medicare Advantage only: local and regional
coordinated care plans, PFFS and MSA. Standalone Part D, employer-only direct-contract PDP, cost
plans and PACE are excluded and do not read across to Medicaid, Commercial or Exchange.
Nothing here is an estimate or a projection. The enrolment file is the market's own record of
what happened, published about four weeks in arrears, and the page is rebuilt from it the day it
lands.
Provenance
Levels and trend — CMS Monthly Enrollment by Plan, 21
files, January 2025 → September 2026.
Product and county — CMS CPSC Contract/Plan/State/County,
August 2026 and September 2026.
Suppression — CPSC masks any cell of ten or fewer as *. That is
416,266 lives, 1.16% of the total, reconciled against
the plan file. County figures sum unsuppressed cells only, so a plan falling below eleven in a
county reads as an exit rather than a decline.
Licence — US Government public domain. No agreement, no cost.
How this page maintains itself
A scheduled job polls from the 3rd until both files land, checks the column set, row count
and total lives against the prior month, then rebuilds this page.
Product mix, county footprint and the posture lines under each card are all derived from the
file. No sentence on this page was written for a particular month except the opening paragraph,
and every figure in that was checked back to the data before it shipped.
Interrupts — a carrier moves more than 2% month on month; an
offsetting county pair suggests a reassignment; the file is five days late.
Built 10 October 2026 from the CMS September 2026 enrolment files.
Lede written from a locked fact block and checked figure by figure against it; every other figure on
this page is computed.