Medicare Advantage

Seattle Medicare Advantage for 2027: how HMO, HMO-POS and PPO shares shift

King County has 59 Medicare Advantage plans for 2027. Compared with 2026, 27 plans are not coming back, 18 are new, and 31 continuing plans changed in some way you should check before December 7, 10 of them under a new name. This guide covers what those numbers mean for Seattle, not which plan to pick.

SEATTLE — Fall 2026. As the Annual Enrollment Period for 2027 coverage opens, the Medicare Advantage lineup in King County — the county Seattle sits in — is leaning more toward HMO-style plans than it did this year. According to the CMS Medicare Advantage Landscape Source File, King County will have 59 Medicare Advantage plans from 11 carriers for 2027, split 30 HMO, 12 HMO-POS and 17 PPO. No plans in the Private Fee-for-Service (PFFS) category are offered in the county for 2027.

That split matters because the plan type — not the brand on the card — sets the basic rules for which doctors you can see, whether you need a referral, and what happens if you get care outside the plan's network.

How the 2027 lineup splits by plan type

For 2027, King County's 59 Medicare Advantage plans break down this way, according to CMS:

• HMO: 30 plans
• HMO-POS: 12 plans
• PPO: 17 plans
• PFFS: none offered

Grouped together, HMO and HMO-POS plans account for 42 of the 59 — a majority of the county's choices. PPOs make up the rest. The full table on this page lists every plan by carrier.

What each plan type actually means

The letters on the end of a plan name describe how the plan works, not how good it is. Here is the plain-English version.

HMO (Health Maintenance Organization). You generally pick a primary care doctor and stay inside the plan's network. Many HMOs ask for a referral before you see a specialist. Out-of-network care is usually not covered except in an emergency or for urgent care while traveling.

HMO-POS (HMO with Point-of-Service). An HMO with a limited exception: for certain services, the plan may pay for care from providers outside the network, often at a higher share of the cost. The specifics vary by plan, so the Evidence of Coverage is the place to check.

PPO (Preferred Provider Organization). You can see any Medicare-approved provider who accepts the plan. Staying in-network costs less; going out-of-network is covered but at a higher cost share. Referrals are typically not required.

PFFS (Private Fee-for-Service). These plans set their own payment terms, and any provider who agrees to those terms can treat you. No PFFS plans are being offered in King County for 2027.

None of these types is cheaper or better in the abstract. The right fit depends on who your doctors are, whether they are in a given plan's network, how often you travel, and how you feel about referrals.

Which carriers offer which types in King County for 2027

From the CMS 2027 landscape file for King County:

• HMO plans are offered by Aetna (CVS Health), AgeRight Advantage, Community Health Plan of WA Medicare Advantage, Devoted Health, Elevance Health (Anthem), Humana, Kaiser Permanente, Molina Healthcare of Washington, Inc., and Regence BlueShield.
• HMO-POS plans are offered by Centene (WellCare) and UnitedHealthcare.
• PPO plans are offered by Aetna (CVS Health), Humana, Regence BlueShield, and UnitedHealthcare.

A carrier may show up in more than one row because it offers more than one type. The table below lists every plan by name and type.

What is changing from 2026 to 2027

Across King County's Medicare Advantage market, 27 plans are not returning for 2027, 18 are new, and 10 have been renamed. If your current plan is renamed or non-renewing, your Annual Notice of Change (ANOC) — mailed in September — explains what is happening and your options. A rename is not a cancellation.

Overall, King County's count moves from 68 Medicare Advantage plans in 2026 to 59 in 2027.

Dates and 2027 figures you can rely on

• Annual Enrollment Period: October 15 – December 7, 2026. Changes take effect January 1, 2027.
• Medicare Advantage Open Enrollment: January 1 – March 31, 2027, for people already in a Medicare Advantage plan.
• Part D out-of-pocket cap: $2,400 in 2027 (up from $2,100 in 2026).
• Part D maximum deductible: $700 in 2027 (up from $615 in 2026).
• 2027 Part B premium, Part B deductible and IRMAA brackets: CMS publishes these later in the fall, typically in November.

How to match a plan type to your situation

A few questions that tend to make the HMO-vs-PPO choice clearer:

• Are the doctors and hospitals you use already in the plan's network? Call them or check the plan's directory.
• Do you spend part of the year outside Washington? That often tilts people toward a PPO because of out-of-network coverage.
• Are you comfortable going through a primary care doctor for specialist referrals, or do you want to self-refer?
• Do you take specific prescriptions? Each plan has its own drug list, regardless of HMO or PPO label.

The Medicare Plan Finder at medicare.gov lets you enter your ZIP code, doctors and prescriptions and see how each plan handles them.