This page explains how Medicare works with the health programs of the Confederated Tribes of Coos, Lower Umpqua and Siuslaw Indians (CTCLUSI). It is published by Benefits Life, a licensed insurance agency. We are not affiliated with the tribe. For tribal eligibility, benefits and current hours, contact the tribe's health programs directly.
Three Rivers Health Center
The tribe's offices are at 1245 Fulton Avenue in Coos Bay (541-888-9577 or 888-280-0726). Its Three Rivers Health Center is at 150 S. Wall Street, Coos Bay. The tribe's announcements say:
- the center opened to tribal members in May 2024 and to the public in July 2024;
- it offers medical, behavioral health, pharmacy, telehealth and laboratory services;
- the tribe's dental clinic, at 1245 Fulton Avenue (541-888-6433), is now Three Rivers Dental Clinic, part of Three Rivers Health Center;
- leaders said the center would serve Coos, Curry and Douglas counties, with plans to expand services to members in Lane and Lincoln counties.
New patients can enroll through the center's website, threerivers.health.
Referred care and Medicare
When you need care the center doesn't provide, ask the tribe's health staff how referred care works for you. Under federal rules, the Indian Health Service, including Purchased/Referred Care, is the payer of last resort: it does not pay when Medicare, Medicaid or other coverage would pay (42 CFR 136.61). With Medicare, outside providers bill Medicare first. Ask before you schedule outside care whether you need approval.
How Medicare works with your CTCLUSI care
- Medicare pays your clinic. CMS says you can keep using your Indian health care provider, and the provider bills Medicare for you.
- Part B. The standard Part B premium is $202.90 a month in 2026. Tribal health care is not employer coverage, so it doesn't let you delay Part B without a late enrollment penalty.
- Part D. Drug coverage from IHS, a tribe or an urban Indian organization counts as creditable coverage, so you won't pay a Part D late penalty for the months you had it (42 CFR 423.56). Every Part D plan must offer contract terms to Indian health pharmacies in its area; ask the Three Rivers pharmacy which plans it works with.
- No special enrollment rules. Tribal members use the same enrollment periods as everyone else. Open Enrollment for 2027 coverage runs October 15 to December 7, 2026.
- Help paying. If your income is limited, you may qualify for a Medicare Savings Program, Extra Help or the Oregon Health Plan.
Medicare plans in Coos County
CMS data list just 1 Medicare Advantage plan open to everyone in Coos County for 2027, and none open to everyone in Curry County, where the only plan is a special needs plan. Ask Three Rivers whether it works with a plan before you enroll; CMS advises checking with your Indian health care provider first. Original Medicare pays any provider in the country that accepts Medicare, and many people add one of the 8 standalone Part D plans sold in Oregon. See Medicare in Coos County, Douglas County and tribal health and Medicare in Oregon.
Where to get help
- Three Rivers Health Center, for questions about your tribal health benefits.
- 1-800-MEDICARE (1-800-633-4227, TTY 1-877-486-2048) or Medicare.gov.
- Social Security, 1-800-772-1213, to sign up for Part A and Part B.
- To compare your options, you can request a call from a licensed insurance agent, or see licensed insurance agents in Oregon.
See all Oregon tribal Medicare guides.
Sources
- Confederated Tribes of Coos, Lower Umpqua and Siuslaw Indians — Opening of Three Rivers Health Center
- Confederated Tribes of Coos, Lower Umpqua and Siuslaw Indians — Three Rivers Health Center announcements
- Confederated Tribes of Coos, Lower Umpqua and Siuslaw Indians — Dental clinic
- Three Rivers Health Center
- CMS — Important Facts about Medicare for American Indians and Alaska Natives
- CMS — Medicare and Tribal Medicare Beneficiaries: Original Medicare and Medicare Advantage
- CMS — CY2027 Medicare Advantage and Part D Landscape files
- 42 CFR 136.61 — Payor of last resort
- 42 CFR 423.56 — Creditable prescription drug coverage
Frequently asked questions
Do CTCLUSI members need to enroll in Medicare?
Medicare is your choice, but tribal health care is not insurance. Medicare covers care anywhere in the country and lets the clinic bill Medicare, and federal rules make IHS-funded referred care the payer of last resort when Medicare or other coverage could pay.
What is Three Rivers Health Center?
It is the tribe's health center at 150 S. Wall Street in Coos Bay, which opened in 2024 with medical, behavioral health, pharmacy, telehealth and lab services. The tribe's dental clinic is now Three Rivers Dental Clinic.
Are there special Medicare enrollment periods for tribal members?
No. American Indians and Alaska Natives use the same Medicare enrollment periods as everyone else: the Initial Enrollment Period around age 65, Open Enrollment from October 15 to December 7, and the Medicare Advantage Open Enrollment Period from January 1 to March 31.
How many Medicare Advantage plans are in Coos County?
CMS data list 1 Medicare Advantage plan open to everyone in Coos County for 2027. Ask Three Rivers whether it works with that plan before you enroll.
Medicare in your Oregon county
Plans, local agents and help, county by county: Multnomah · Washington · Clackamas · Lane · Marion · Jackson · Deschutes · Linn · Douglas · Yamhill · Benton · Polk · Josephine · Umatilla · Klamath · Coos · Columbia · Lincoln · Clatsop · Malheur · All 36 counties →
