Which counties have growth momentum with almost no competition?
8 of the 76 tracked counties combine 2 or fewer MA carriers with positive penetration velocity: growth is arriving, and almost nobody is there to sell against. Every one of them is also a flagged low-competition market in the county file, which makes this the expansion whitespace list for the tracked set.
The whitespace list
Bars show current penetration; the annotation carries carrier count and YoY velocity. Low penetration plus positive velocity plus an empty shelf is the expansion signal.
| County | State | Carriers | Penetration | Velocity (pts YoY) | D-SNP share | OM base (K) | Incumbent to beat |
|---|---|---|---|---|---|---|---|
| Towns | GA | 2 | 66.4% | +0.87 | 12% | 12 | Humana |
| Lubbock | TX | 2 | 56.8% | +0.87 | 20% | 72 | UHC |
| Coconino | AZ | 2 | 52.6% | +0.87 | 24% | 48 | UHC |
| Ashtabula | OH | 2 | 47.8% | +0.87 | 22% | 68 | UHC |
| Benzie | MI | 2 | 46.2% | +0.87 | 16% | 22 | BCBSMich |
| Greene | NC | 2 | 44.8% | +0.87 | 26% | 28 | Centene |
| LaSalle | IL | 2 | 43.2% | +0.87 | 18% | 92 | BCBS |
| Crawford | PA | 2 | 44.2% | +0.8 | 16% | 78 | Highmark |
Coverage: what this list can and cannot see
These counties come from the 76-county tracked set compiled from CPSC files, chosen for signal value, not randomness. Rural whitespace outside the tracked set is invisible here until the full-county CPSC pipeline lands (see the roadmap card on the sales hub). Treat this as a verified starter list, not the census of American MA whitespace.
So what / Now what
In a two-carrier county with rising penetration, demand is growing faster than the shelf. A new entrant is not fighting for share, it is absorbing demand the incumbents cannot brand-block, and brokers in these counties have almost nothing to sell. The same table works defensively: if you are one of the two incumbents, these are the counties where a rival filing should trigger a retention plan.
- Network and product teams: these counties are service-area expansion candidates where filing plus a modest network buys a visible market position.
- Broker channel: recruit in these counties first; agents with two carriers on the shelf will lead with a third that pays attention to them.
- Check the top-carrier column before entering: selling against one entrenched incumbent differs from splitting a fragmented duopoly.
- Coverage caveat: this is the 76-county tracked set, not all ~3,100 counties. The full whitespace map arrives with the complete CPSC pipeline (roadmap).
Provenance — County-level MA market snapshot (76 tracked counties)
- Source file
- CMS MA Enrollment by State/County/Plan (CPSC monthly files)
- Vintage
- Plan year 2026, with 2023–2026 penetration history
- Last updated
- May 1, 2026
- Refresh cadence
- Monthly (pipeline pending; currently a curated extract)
- Method
- Penetration, D-SNP share, carrier count and top carrier per county compiled from CPSC files for 76 high-signal counties.
- Known limitations
- Covers 76 tracked counties, not all ~3,100. Velocity = simple YoY penetration point change.