CMS Medicare enrollment · June 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
- 416.7K
- Original Medicare
- 225.3K
- MA & Other share
- 45.9%
- Part D coverage
- 78.2%
416,679
225,327 beneficiaries
CMS combined delivery-system measure
325,716 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 | 106,775 | 47,613 | 59,162 | 55.4% | 80.4% |
| Adams County | 1,618 | 1,039 | 579 | 35.8% | 76.3% |
| Bannock County | 17,891 | 9,533 | 8,358 | 46.7% | 76.4% |
| Bear Lake County | 1,659 | 1,469 | 190 | 11.5% | 75.8% |
| Benewah County | 3,278 | 2,703 | 575 | 17.5% | 70.6% |
| Bingham County | 9,481 | 5,517 | 3,964 | 41.8% | 77.3% |
| Blaine County | 6,375 | 5,015 | 1,360 | 21.3% | 81.8% |
| Boise County | 2,567 | 1,191 | 1,376 | 53.6% | 76.3% |
| Bonner County | 15,933 | 9,724 | 6,209 | 39% | 74% |
| Bonneville County | 22,787 | 14,061 | 8,726 | 38.3% | 79.8% |
| Boundary County | 4,149 | 2,828 | 1,321 | 31.8% | 70% |
| Butte County | 758 | 703 | 55 | 7.3% | 71.4% |
| Camas County | 326 | 210 | 116 | 35.6% | 75.8% |
| Canyon County | 49,524 | 18,627 | 30,897 | 62.4% | 81.2% |
| Caribou County | 1,527 | 1,240 | 287 | 18.8% | 76.4% |
| Cassia County | 4,619 | 2,816 | 1,803 | 39% | 79.5% |
| Clark County | 140 | 101 | 39 | 27.9% | 73.6% |
| Clearwater County | 3,072 | 2,597 | 475 | 15.5% | 68.1% |
| Custer County | 1,512 | 1,272 | 240 | 15.9% | 70.6% |
| Elmore County | 5,651 | 3,091 | 2,560 | 45.3% | 61.1% |
| Franklin County | 2,807 | 1,879 | 928 | 33.1% | 77.2% |
| Fremont County | 2,926 | 2,037 | 889 | 30.4% | 77.4% |
| Gem County | 5,886 | 2,276 | 3,610 | 61.3% | 79.4% |
| Gooding County | 3,506 | 1,781 | 1,725 | 49.2% | 79.3% |
| Idaho County | 5,648 | 4,652 | 996 | 17.6% | 70.6% |
| Jefferson County | 5,309 | 3,330 | 1,979 | 37.3% | 78.8% |
| Jerome County | 4,279 | 1,981 | 2,298 | 53.7% | 79.4% |
| Kootenai County | 48,717 | 28,440 | 20,277 | 41.6% | 76.2% |
| Latah County | 7,675 | 5,761 | 1,914 | 24.9% | 77.3% |
| Lemhi County | 2,999 | 2,728 | 271 | 9% | 71.4% |
| Lewis County | 1,839 | 1,588 | 251 | 13.6% | 71.5% |
| Lincoln County | 978 | 511 | 467 | 47.8% | 75.3% |
| Madison County | 4,058 | 2,745 | 1,313 | 32.4% | 81.8% |
| Minidoka County | 4,557 | 2,612 | 1,945 | 42.7% | 79.4% |
| Nez Perce County | 11,062 | 8,629 | 2,433 | 22% | 78.3% |
| Oneida County | 1,164 | 907 | 257 | 22.1% | 72.9% |
| Owyhee County | 2,707 | 1,167 | 1,540 | 56.9% | 76.4% |
| Payette County | 6,601 | 2,951 | 3,650 | 55.3% | 79.6% |
| Power County | 1,595 | 1,044 | 551 | 34.5% | 73.9% |
| Shoshone County | 4,034 | 2,682 | 1,352 | 33.5% | 73.3% |
| Teton County | 2,131 | 1,840 | 291 | 13.7% | 79.9% |
| Twin Falls County | 19,471 | 8,586 | 10,885 | 55.9% | 80% |
| Unknown | Not reported | Not reported | Not reported | Not reported | Not reported |
| Valley County | 3,646 | 2,085 | 1,561 | 42.8% | 78.6% |
| Washington County | 3,442 | 1,765 | 1,677 | 48.7% | 79% |
Source and interpretation
CMS Medicare Monthly Enrollment, June 2026, published 2026-09-23. “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.