Medicare plan leaving Asotin County: choosing coverage when care spans two states

In Asotin County, the doctor's office might be in Washington and the hospital in Idaho, or the other way around. The county sits in the far southeast corner of the state, bordered by Nez Perce County, Idaho, across the Snake River and by Wallowa County, Oregon, to the south. That two-state reality is the first thing to think about if your Medicare Advantage plan has told you it is leaving the county after December 31, 2026.

Care that crosses the Snake River

CMS's hospital file lists one hospital in Asotin County: Tri-State Memorial Hospital in Clarkston, a critical access hospital on Highland Avenue. Across the bridge, the same file lists St. Joseph Regional Medical Center in Lewiston, Idaho, as an acute care hospital. Local transit treats the valley as one place, too: Asotin County's public transit and Lewiston's system share routes and transfer points on both sides of the river.

Here is why that matters for your choice:

• A Medicare Advantage plan sold in Asotin County has a network and a service area. Before joining one for 2027, ask specifically whether your Lewiston doctors and the Lewiston hospital are in network, not just the Clarkston providers. Don't assume a Washington plan's network stops or continues at the state line; ask.
• Original Medicare has no network. It pays any doctor or hospital in the U.S. that accepts Medicare, in Idaho or Washington alike. For a household that already splits care between Clarkston and Lewiston, that's a real point in its favor, though Original Medicare alone has no annual out-of-pocket limit.

Asotin County's Medicare numbers

Sources: CMS Medicare Monthly Enrollment, July 2026; WA OFM population by age, April 1, 2025 (county population 22,950 on April 1, 2026).

Nearly three in four Asotin beneficiaries use Original Medicare, and more than half of all beneficiaries here carry a stand-alone Part D plan.

The disability figure stands out. Asotin has the second-highest share of under-65 beneficiaries among Washington's 39 counties. If that's you, read the Medigap section with care.

Then there are the 1,743 people whose prescriptions come through a Medicare Advantage plan. For anyone in that group whose plan is the one leaving, the drug benefit ends on December 31 along with everything else. A stand-alone Part D plan has to be chosen separately if you move to Original Medicare; it won't appear on its own unless you get Extra Help. Check that your pharmacy, whether it's in Clarkston or Lewiston, is in the Part D plan's network before you enroll, since drug plans have pharmacy networks too. In 2027 no Part D plan can charge a deductible above $700, and your out-of-pocket spending on covered drugs is capped at $2,400 for the year.

The 2027 rules, in the order you'll need them

This year: nothing changes. Your plan stays responsible for your coverage through December 31, 2026, so keep your appointments and refills on schedule.

By December 31: pick your 2027 coverage. Anything chosen by then, whether during Open Enrollment (October 15 to December 7) or after, starts January 1.

If you miss it: because your plan is ending, you have a special enrollment period from December 8, 2026 through February 28, 2027. January enrollments begin February 1; February enrollments begin March 1. If you didn't choose anything at all, Medicare puts you in Original Medicare on January 1 without a drug plan. People with Extra Help are reassigned by CMS to a stand-alone Part D plan.

Medigap: choosing Original Medicare gives you a guaranteed issue right under Washington's RCW 48.66.055. It's a Washington right for Washington residents, so it's the Washington list of plans that applies: Plans A through F (including high-deductible F), K or L if you were first eligible for Medicare before 2020, or A, B, D, G (including high-deductible G), K or L if you were first eligible on or after January 1, 2020. OIC says to apply on or after November 1; the right expires March 4, 2027. Choose another Medicare Advantage plan and you don't get it.

Under 65: As we read it, Washington's statute sets no age cutoff for this right, but insurers only have to offer policies they sell to new enrollees, and federal law doesn't require Medigap sales to people under 65. OIC says options for this group are more limited. Call SHIBA and get a firm answer from an insurer before you leave Medicare Advantage.

Our statewide guide has the citations and the paperwork list.

Help in the valley

SHIBA. Asotin County's SHIBA sponsor is the WA-ID Volunteer Center, whose office is at 1424 Main Street in Lewiston, Idaho, with a listed number of 208-746-7787 (Monday through Thursday, 8 a.m. to 5 p.m.). OIC lists it as part of Washington's SHIBA program even though the office is across the state line. On October 26, OIC's directory showed the listing as not accepting appointments and directed people to 1-800-MEDICARE (1-800-633-4227). Washington's statewide SHIBA line, 800-562-6900, takes calls weekdays from 8:30 to 4:30.

Aging and disability services. Southeast Washington Aging and Long Term Care is the Area Agency on Aging, and its Community Living Connections office is in Clarkston at 744 Fifth Street, Suite C (509-758-2355, voice and TDD).

Getting to appointments. Asotin County Public Transit (1494 Poplar Street, Clarkston, 509-758-3567) runs routes in Asotin County and into Lewiston. Its half fare card is open to people 62 and older and to anyone who shows a Medicare card. The transit agency's medical transport list also names Interlink, a volunteer driver program, at 509-751-9143.

Paying for it. Medicare Savings Programs through Washington's Health Care Authority have no asset test; apply at washingtonconnection.org. Approval also qualifies you for Extra Help with prescriptions.

What I'd do this month

1. List every provider you use and mark which state each is in.
2. Run your prescriptions through Medicare Plan Finder for 2027, using your Asotin County home ZIP code, since plans are offered by where you live.
3. If Original Medicare is your direction, apply for Part D and any Medigap policy in November so both start January 1.
4. Keep the plan's letter with its postmarked envelope; a Medigap insurer may ask for it.

Your plan's notices fix your own dates, federal Medicare rules and Washington law decide your rights, and 1-800-MEDICARE, SHIBA or a licensed agent can confirm how both apply before you make a final call.

Related pages: Washington statewide guide

Asotin County questions

Sources

1. CMS Medicare Monthly Enrollment, July 2026
2. WA OFM population estimates
3. U.S. Census Bureau County Adjacency File
4. WA DOH hospital data
5. CMS Hospital General Information
6. WA OIC: Medicare Advantage plan changing or leaving
7. WA OIC: Find a local SHIBA office
8. RCW 48.66.055
9. Medicare: Choosing a Medigap Policy (2026)
10. CMS CY 2027 Enrollment and Disenrollment Guidance
11. Lewiston Transit and Asotin County PTBA: Half Fare Card
12. HCA: Medicare Savings Program