CMS Medicare enrollment · April 2026
Idaho Medicare Enrollment
State and county enrollment from CMS, including Original Medicare, Medicare Advantage and Other Health Plans, and Part D coverage.
Informational only. These enrollment counts do not compare plans or provide medical, financial, or enrollment advice.
Idaho enrollment figures
- Total Medicare enrollment
- 413.9K
- Original Medicare
- 223.4K
- MA & Other share
- 46%
- Part D coverage
- 78.3%
413,924
223,352 beneficiaries
CMS combined delivery-system measure
323,961 beneficiaries
County enrollment
45 CMS county rows for Idaho. Unavailable values remain marked as not reported rather than estimated.
| County | Total | Original Medicare | MA & Other | MA & Other share | Part D share |
|---|---|---|---|---|---|
| Ada County | 105,916 | 47,020 | 58,896 | 55.6% | 80.4% |
| Adams County | 1,621 | 1,044 | 577 | 35.6% | 75.9% |
| Bannock County | 17,807 | 9,452 | 8,355 | 46.9% | 76.7% |
| Bear Lake County | 1,646 | 1,461 | 185 | 11.2% | 75.8% |
| Benewah County | 3,275 | 2,701 | 574 | 17.5% | 70.9% |
| Bingham County | 9,429 | 5,469 | 3,960 | 42% | 77.5% |
| Blaine County | 6,350 | 4,987 | 1,363 | 21.5% | 81.8% |
| Boise County | 2,560 | 1,188 | 1,372 | 53.6% | 76% |
| Bonner County | 15,812 | 9,620 | 6,192 | 39.2% | 74.3% |
| Bonneville County | 22,602 | 13,927 | 8,675 | 38.4% | 79.9% |
| Boundary County | 4,142 | 2,817 | 1,325 | 32% | 70.3% |
| Butte County | 761 | 709 | 52 | 6.8% | 71.5% |
| Camas County | 322 | 206 | 116 | 36% | 76.1% |
| Canyon County | 49,078 | 18,363 | 30,715 | 62.6% | 81.4% |
| Caribou County | 1,518 | 1,231 | 287 | 18.9% | 76.9% |
| Cassia County | 4,589 | 2,791 | 1,798 | 39.2% | 79.5% |
| Clark County | 137 | 100 | 37 | 27% | 73% |
| Clearwater County | 3,061 | 2,595 | 466 | 15.2% | 67.9% |
| Custer County | 1,512 | 1,276 | 236 | 15.6% | 70.8% |
| Elmore County | 5,616 | 3,062 | 2,554 | 45.5% | 61.2% |
| Franklin County | 2,782 | 1,867 | 915 | 32.9% | 77.4% |
| Fremont County | 2,912 | 2,032 | 880 | 30.2% | 77.3% |
| Gem County | 5,850 | 2,260 | 3,590 | 61.4% | 79.3% |
| Gooding County | 3,520 | 1,795 | 1,725 | 49% | 79.2% |
| Idaho County | 5,623 | 4,643 | 980 | 17.4% | 70.5% |
| Jefferson County | 5,267 | 3,300 | 1,967 | 37.3% | 78.9% |
| Jerome County | 4,242 | 1,950 | 2,292 | 54% | 79.7% |
| Kootenai County | 48,329 | 28,103 | 20,226 | 41.9% | 76.3% |
| Latah County | 7,625 | 5,706 | 1,919 | 25.2% | 77.6% |
| Lemhi County | 2,984 | 2,719 | 265 | 8.9% | 71.6% |
| Lewis County | 1,834 | 1,586 | 248 | 13.5% | 71.3% |
| Lincoln County | 968 | 502 | 466 | 48.1% | 75.6% |
| Madison County | 4,024 | 2,733 | 1,291 | 32.1% | 81.7% |
| Minidoka County | 4,531 | 2,592 | 1,939 | 42.8% | 79.7% |
| Nez Perce County | 11,056 | 8,613 | 2,443 | 22.1% | 78.4% |
| Oneida County | 1,158 | 905 | 253 | 21.8% | 73.1% |
| Owyhee County | 2,677 | 1,164 | 1,513 | 56.5% | 76% |
| Payette County | 6,600 | 2,943 | 3,657 | 55.4% | 79.6% |
| Power County | 1,585 | 1,042 | 543 | 34.3% | 74.4% |
| Shoshone County | 4,038 | 2,690 | 1,348 | 33.4% | 73.2% |
| Teton County | 2,115 | 1,822 | 293 | 13.9% | 80.3% |
| Twin Falls County | 19,385 | 8,538 | 10,847 | 56% | 80.1% |
| Unknown | Not reported | Not reported | Not reported | Not reported | Not reported |
| Valley County | 3,628 | 2,069 | 1,559 | 43% | 78.5% |
| Washington County | 3,437 | 1,759 | 1,678 | 48.8% | 79.1% |
Source and interpretation
CMS Medicare Monthly Enrollment, April 2026, published 2026-07-23. “MA & Other” retains the official combined CMS field label.
- CMS suppresses some small counts with an asterisk; suppressed values remain null in this snapshot.
- Medicare Advantage and Other Health Plans is the CMS-published combined measure and is not limited to Medicare Advantage alone.
- Enrollment counts describe a reporting month and do not compare plan benefits, provider networks, quality, or personal costs.