The first big Medicare decision most Oregonians make is structural: stay with Original Medicare (usually with a Medigap policy and a stand-alone Part D plan), or join a Medicare Advantage plan that bundles coverage. Oregon is close to evenly split: in July 2026, 523,528 people were in Medicare Advantage or other health plans and 450,352 were in Original Medicare (CMS). Neither is right for everyone; it depends on your health, your doctors, your county, your travel and your budget.
Side-by-side snapshot
| Original Medicare + Medigap + Part D | Medicare Advantage (with Part D) | |
|---|---|---|
| Monthly premiums | Part B premium + Medigap premium + Part D premium | Part B premium + the plan's premium, if any |
| What you pay when you get care | Depends on the Medigap letter; with Plan G, mainly the yearly Part B deductible ($283 in 2026) | The plan's deductibles, copayments and coinsurance |
| Yearly limit on medical costs | None in Original Medicare alone; Medigap pays most or all of your share | Up to $9,850 in network in 2027 (plans can set lower) |
| Provider choice | Any U.S. provider who accepts Medicare | Plan network; PPOs cover out-of-network at a higher cost |
| Referrals | Not needed | Often required in HMOs |
| Prior authorization | Rare | Common for some services |
| Drug coverage | Separate Part D plan | Usually built in |
| Dental, vision, hearing | Not covered by Original Medicare or Medigap | May be offered; varies by plan |
| Out-of-state care | Same as in Oregon | Emergency and urgent care; other care depends on the plan |
| Where it's available in Oregon | Every county | Depends on your county; no plan open to everyone in Grant, Harney, Lake, Umatilla or Union for 2027 |
Medicare Advantage plans may offer extra benefits such as dental, vision, hearing or fitness. Extra benefits vary by plan and county, may have limits and costs, and not every plan offers them. Check a plan's Summary of Benefits or Evidence of Coverage.
How costs work on each path
The two paths spread your costs differently:
- Original Medicare with Medigap: you pay more each month in premiums (Part B, Medigap and Part D), and in exchange most of your Medicare-covered costs are paid when you use care. With Plan G, after the Part B deductible you usually owe nothing more for Medicare-covered services. Your costs are about the same in a healthy year and a year with a hospital stay.
- Medicare Advantage: monthly premiums are often lower, and you pay copayments or coinsurance when you use care, such as a daily hospital copayment or specialist copayments. In a healthy year you may pay little; in a year with a hospital stay, surgery or many specialist visits, you could pay up to the plan's yearly limit (at most $9,850 in network in 2027).
- Drugs: on either path, the Part D cap limits what you pay for covered drugs to $2,400 in 2027.
You can't know in advance whether next year will be healthy or not. A practical test: add up a plan's premiums for the year, then add what you'd pay in a bad year (the plan's out-of-pocket limit for Medicare Advantage, or the Medigap plan's deductible or limit). Compare that worst case, not just the premium. See plans for your ZIP code on PlanMatch to compare the plans actually offered where you live.
Provider freedom
With Original Medicare and Medigap, you pick a doctor who accepts Medicare and go: no network, no referrals, and prior authorization only for a short list of services. That matters if you see specialists in more than one health system, travel from rural Oregon to Portland, Eugene or out of state for care, or split the year between Oregon and another state.
With Medicare Advantage, you pick a plan and use its network and rules. Networks can change during the year: if a doctor leaves, the plan must notify you in writing at least 45 days ahead for primary care and behavioral health providers and 30 days for other specialists you see regularly (42 CFR 422.111(e)). Check that your doctors, hospital and pharmacy are in the network before you join, every year.
Rules, prior authorization and networks
Medicare Advantage plans can require prior authorization, often for imaging, specialty drugs, surgery, skilled nursing and home health. Federal rules have tightened this: since 2024, plans must follow Original Medicare's coverage rules when deciding what is medically necessary, and from 2026 they must decide prior authorization requests within 72 hours for urgent requests and 7 days for standard ones. If a plan denies care, you can appeal; see Medicare appeals in Oregon.
Travel and snowbird considerations
If you spend part of the year outside Oregon, the structural difference matters a lot:
- Original Medicare with Medigap works the same in every state with any provider who accepts Medicare. Medigap Plans C, D, F, G, M and N also pay 80% of emergency care outside the U.S. during the first 60 days of a trip, after a $250 deductible, up to a $50,000 lifetime limit.
- Medicare Advantage HMOs generally cover only emergency and urgent care outside the service area.
- Medicare Advantage PPOs cover out-of-network care at a higher cost.
- Some plans offer visitor or travel benefits in other areas; get the details in writing. See can I use my Medicare Advantage plan outside Oregon?
Where you live in Oregon matters
Medicare Advantage plans are approved county by county. For 2027, Multnomah, Washington and Clackamas counties have 32, 32 and 32 plans open to everyone, Deschutes County has 3, Coos County has 1, Curry County has only a special needs plan, and Grant, Harney, Lake, Umatilla and Union counties have none (CMS 2027 Landscape). In those counties, Original Medicare with Medigap and a Part D plan is the main way to fill Medicare's gaps unless you have employer, retiree, VA or other coverage. See your county.
Some companies stop offering Medicare Advantage plans in some Oregon counties for 2027. If yours is ending, see Oregon plans ending in 2027: you have a Special Enrollment Period through February 28, 2027 and a Medigap guaranteed-issue right for 63 days after the plan ends.
What changes when life changes
If you start on Medicare Advantage and later want Original Medicare with Medigap, you can switch during Open Enrollment, but a Medigap company in Oregon can usually ask health questions and turn you down. The exceptions: you're within your 12-month trial right, you have a guaranteed-issue right (your plan leaves your county or you move out of its area), or you're in your Medigap open enrollment period. Oregon's yearly birthday rule helps only people who already have Medigap. See can I switch from Medicare Advantage to Medigap in Oregon?
Going the other way, from Original Medicare to Medicare Advantage, is possible every Open Enrollment, with no health questions (in a county where plans are offered).
A simple decision framework
Original Medicare with Medigap is often a better fit if:
- You travel often or live part of the year outside Oregon
- You see specialists in more than one health system, or travel for care
- You value predictable yearly costs over a lower monthly premium
- You don't want referrals or most prior authorization
- You live in a county with few or no Medicare Advantage plans
- You can afford Medigap and Part D premiums, and you're in a window where you can buy Medigap without health questions
Medicare Advantage is often a better fit if:
- You want lower monthly premiums and are comfortable paying copayments as you use care
- Your doctors, hospital and pharmacy are in a plan's network
- You want drug coverage and Medicare in one plan
- You qualify for a special needs plan, for example because you have both Medicare and the Oregon Health Plan
To compare both paths for your doctors, prescriptions and county with plans from the companies they work with, you can request a call from a licensed insurance agent, or meet licensed insurance agents in Oregon.
Related guides
- Medigap in Oregon
- Medicare Advantage (Part C) in Oregon
- Part D in Oregon
- How do I choose a Medicare plan in Oregon?
Sources
- Medicare.gov — Compare Original Medicare and Medicare Advantage
- Medicare.gov — Health plans
- Medicare.gov — When can I buy Medigap?
- 42 CFR 422.111 — Disclosure requirements, including notice of provider network changes (Cornell LII)
- CMS — Interoperability and Prior Authorization final rule (CMS-0057-F)
- CMS — 2024 Medicare Advantage and Part D final rule (CMS-4201-F), coverage criteria
- CMS — Medicare Advantage announcements and documents (CY2027 out-of-pocket limits)
- CMS — Medicare Advantage and Part D contract and enrollment data (CY2027 Landscape, Oregon plan counts)
- CMS — Medicare Monthly Enrollment (Oregon)
- Oregon Secretary of State — OAR 836-052-0142, Medigap guaranteed issue
- Oregon Secretary of State — OAR 836-052-0143, Medigap birthday rule
Frequently asked questions
What is the difference between Medicare Advantage and Original Medicare?
Original Medicare is the federal program (Part A and Part B): you can use any provider in the U.S. who accepts Medicare, there's no yearly limit on your share of costs, and you add Medigap and a Part D plan if you want them. Medicare Advantage is a private plan approved by Medicare that covers the same services, usually includes drug coverage, uses a network and prior authorization, and has a yearly out-of-pocket limit.
Is Original Medicare or Medicare Advantage cheaper in Oregon?
It depends on how much care you use and the plans in your county. Medicare Advantage often has lower monthly premiums, but you pay copayments as you use care, up to the plan's yearly limit ($9,850 at most in network in 2027). Original Medicare with Medigap has higher monthly premiums but, depending on the plan letter, leaves little or nothing to pay when you use care. Compare total yearly costs for the plans available to you.
Can I switch from Medicare Advantage to Original Medicare later in Oregon?
Yes, during Open Enrollment (October 15 to December 7) or the Medicare Advantage Open Enrollment Period (January 1 to March 31). But buying a Medigap policy when you switch usually requires health questions in Oregon, and you can be turned down, unless you have a guaranteed-issue right such as your plan leaving your county or the 12-month trial right.
Which is better for snowbirds and people who travel?
Original Medicare with Medigap usually works better, because it covers care from any Medicare provider in every state. Medicare Advantage HMOs usually cover only emergency and urgent care outside the service area, and PPOs cover out-of-network care at a higher cost.
How many Oregonians have Medicare Advantage vs. Original Medicare?
In July 2026, CMS counted 523,528 Oregonians in Medicare Advantage or other Medicare health plans and 450,352 in Original Medicare, out of 973,880 people with Medicare.
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 →
