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  1. 🏠
  2. Medicare Advantage Plans
  3. California
  4. Contra Costa County

2027 Medicare Advantage Plans in Contra Costa County, CA

Last update: October 5, 2026.

For 2027, Contra Costa County, CA includes 5 Medicare Advantage plans. Enrollment across these plans totals approximately 64,611, with 2 $0 premium options and (2027 Star Ratings Coming Soon) rated 4 stars or higher.

This page and its statistics exclude Medicare Advantage Special Needs Plans (SNPs). Special Needs Plans in Contra Costa County, CA are summarized separately. Visit Medicare Options in Contra Costa County, CA to see more options.

  • PPO Plans
  • HMO Plans

At a Glance

County-level summary of Medicare Advantage plan availability and enrollment based on CMS data.

  • Average Monthly Premium: $44.00/mo
  • $0 Premium Plans: 2
  • Average MOOP: $3,989 ($9,250 max. in 2027)
  • Star Ratings (Plan Mix): (2027 Star Ratings Coming Soon)
  • Average Part D Deductible: $175.00
  • Total MA/MAPD Enrollment: 64,611
  • Plans with the Highest Enrollment
    (as of October 5, 2026)
    1. Kaiser Permanente Sr Adv Enhanced Contra Costa (HMO) — 35,172 enrollees
    2. Kaiser Permanente Sr Adv Basic Contra Costa (HMO) — 18,480 enrollees
    3. HumanaChoice H5525-084 (PPO) — 8,642 enrollees

Medicare Advantage PPO Plans

Preferred Provider Organization (PPO) plans allow members to choose care from both in-network and out-of-network providers. Out-of-network care usually costs more, but PPOs offer greater flexibility in how members access care.

Total PPO Plans
1
Average Monthly Premium
$93.00/mo
Total PPO Enrollment
8,642
$0 Premium PPO Plans
0
Average MOOP
$6,750
Top PPO by Enrollment
HumanaChoice H5525-084 (PPO) — 8,642 enrollees
PPO Plans Without Drug Coverage
0

2027 PPO Medicare Advantage plans in Contra Costa County, California (comparison chart)
Plan Name CMS Stars* Premium/Mo MOOP Rx Ded. CMS ID
HumanaChoice H5525-084
☆☆☆☆☆
$93 $6,750 $700 H5525-084-0
What is the average monthly premium for PPO plans in Contra Costa?
PPO plans in Contra Costa cost $93.00 per month on average.
Which PPO plan has the highest enrollment in Contra Costa?
The most popular PPO plan in Contra Costa is HumanaChoice H5525-084 (PPO), with 8,642 enrollees.
How many PPO plans in Contra Costa do not include prescription drug coverage?
0 PPO plans in Contra Costa do not include prescription drug coverage.

Medicare Advantage HMO Plans

Health Maintenance Organization (HMO) plans are built around a defined network of doctors and hospitals. Care is generally covered only within the network, except in emergencies, but this structure often results in lower premiums and out-of-pocket costs.

Total HMO Plans
4
Average Monthly Premium
$31.75/mo
Total HMO Enrollment
55,969
$0 Premium HMO Plans
2
Average MOOP
$3,299
Top HMO by Enrollment
Kaiser Permanente Sr Adv Enhanced Contra Costa (HMO) — 35,172 enrollees
HMO Plans Without Drug Coverage
1

2027 HMO Medicare Advantage plans in Contra Costa County, California (comparison chart)
Plan Name CMS Stars* Premium/Mo MOOP Rx Ded. CMS ID
Imperial Courage Plan
☆☆☆☆☆
$0 $2,999 N/A H5496-016-0
Imperial Dynamic Plan
☆☆☆☆☆
$0 $295 $0 H5496-012-0
Kaiser Permanente Sr Adv Basic Contra Costa
☆☆☆☆☆
$29 $6,000 $0 H0524-061-0
Kaiser Permanente Sr Adv Enhanced Contra Costa
☆☆☆☆☆
$98 $3,900 $0 H0524-033-0
What is the total number of HMO plans offered in Contra Costa?

There are 4 HMO plans in 2027, covering 55,969 enrollees.

How much do HMO plans cost in Contra Costa?

The average HMO premium in Contra Costa is $31.75 per month, with 2 plans offering $0 premiums.

What is the top HMO by enrollment in Contra Costa?

Kaiser Permanente Sr Adv Enhanced Contra Costa (HMO) is the top HMO in Contra Costa, with 35,172 enrollees.

What is the number of HMO plans without Part D coverage in Contra Costa?

1 HMO plans in Contra Costa do not include prescription drug coverage.

CMS quality ratings for Medicare Advantage plans in Contra Costa County, CA (2027) are summarized below.

Medicare Advantage Plan Ratings in Contra Costa County, CA (2027)
Rating Category Number of Plans Percent of Plans
5 Stars (2027 Star Ratings Coming Soon) (2027 Star Ratings Coming Soon)
4 Stars (includes 5 Stars) (2027 Star Ratings Coming Soon) (2027 Star Ratings Coming Soon)
3 Stars (2027 Star Ratings Coming Soon) (2027 Star Ratings Coming Soon)
Below 3 Stars (2027 Star Ratings Coming Soon) (2027 Star Ratings Coming Soon)
Not Rated (2027 Star Ratings Coming Soon) (2027 Star Ratings Coming Soon)
Average Rating (2027 Star Ratings Coming Soon)

* CMS assigns Medicare Advantage star ratings annually based on plan quality and performance measures.

Primary CMS datasets used for this Medicare Advantage Plan county resource.
Data Source Publisher CMS Version
Landscape Source Files Centers for Medicare & Medicaid Services CY2027 Landscape (202609.1)
Medicare Part C & D Performance Centers for Medicare & Medicaid Services 2027 Star Ratings Data Tables
Plan Benefits Package Centers for Medicare & Medicaid Services PBP Benefits-2027
Monthly Enrollment by Contract/Plan/State/County Centers for Medicare & Medicaid Services 2026-09

All plan counts, enrollment totals, averages, and percentage distributions are calculated at the county level using CMS data and include standard Medicare Advantage (MA/MAPD) plans only, based on a consistent aggregation methodology.

Data sources and methodology documentation.

Secondary Medicare references and explanatory resources.
Publisher Reference Last Accessed
Medicare.gov Understanding Medicare Advantage Plans 25 May, 2025
Medicare.gov Compare Original Medicare & Medicare Advantage 25 May, 2025
NCOA.org 5 Steps to Choosing the Right Medicare Plan for You 25 May, 2025

MedicarePlans.com is an independent informational resource and has no affiliation with, or endorsement from, the U.S. Government or the federal Medicare program.

Data provenance is documented in accordance with the U.S. Core Data for Interoperability (USCDI) Provenance standard .

Page content independently curated and maintained by David W. Bynon, Editorial Steward, using a standardized, data-driven methodology for accurate, non-commercial Medicare plan interpretation and resolution.

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