Fact Sheets Feb 04, 2026

2026 Medicare Accountable Care Organization Initiatives Participation Highlights

Accountable Care Organizations (ACOs)
Administration

2026 Medicare Accountable Care Organization Initiatives Participation Highlights
Increased Participation in ACOs This Year Will Help Medicare be More Accountable for Cost and Quality

CMS continues to bring accountable care to more people with Medicare in 2026, expanding the benefits of high-quality, whole-person health care to achieve better health outcomes for millions of older Americans.

As of January 2026, 14.3 million Medicare beneficiaries are estimated to receive care coordinated by Accountable Care Organizations (ACOs), up from 13.7 million in 2025, representing a 4.4% increase. This includes patients whose health care providers are in Medicare Shared Savings Program (Shared Savings Program) ACOs and entities participating in Center for Medicare and Medicaid Innovation (CMS Innovation Center) accountable care models, as well as other CMS Innovation Center models focused on total cost of care, advanced primary care, and specialty care.

ACOs are groups of doctors, hospitals, and other health care providers who collaborate and provide coordinated, high-quality care to people with Medicare, and they are a critical tool to help Make America Healthy Again by supporting whole person care that addresses prevention, chronic illness and the root causes of disease.

In addition to improving health care, ACOs save billions of dollars for the Medicare program by focusing on delivering the right care at the right time while avoiding unnecessary services and medical errors. ACOs achieve savings because health care providers are held accountable for saving money and improving health care quality, delivering a win for both patients and the Medicare Trust Funds.

To preserve the program for future generations, the Trump Administration has made cutting waste and emphasizing health outcomes in Medicare a top priority. Health care organizations eager to take on more accountability for providing better health care and reducing unnecessary costs can choose the CMS program that’s most appropriate for them and their patients, whether it’s the Shared Savings Program or a CMS Innovation Center pilot program (model). When an ACO succeeds in both delivering high-quality care and spending health care dollars more wisely, the ACO may be eligible to share in the savings it achieves for the Medicare program. Provision of accountable care reduces care fragmentation and lowers health care costs for people with Medicare as they may be able to avoid costly emergency department visits or repeated tests. ACOs also may share in losses if they increase spending.

In Performance Year 2024, the most recently reconciled performance year, Shared Savings Program ACOs earned shared savings totaling $4.1 billion and saved Medicare $2.5 billion. The Trump Administration continues to grow ACO participation through changes to the Shared Savings Program and CMS Innovation Center models: 

  • In 2026, 82.8% of Shared Savings Program ACOs are in Level E of the BASIC track or the ENHANCED track, both of which meet the criteria to be an Advanced Alternative Payment Model (Advanced APM) under the Quality Payment Program. This is the highest percentage since 2012, the inception of the Shared Savings Program, and demonstrates ACO readiness to take on performance-based risk.
  • CMS finalized changes in the CY 2026 Physician Fee Schedule Final Rule that are intended to increase the number of Shared Savings Program ACOs participating in two-sided risk — in which organizations are accountable for losses as well as savings.
  • The ACO REACH Model updated its financial methodology in 2025 to ensure future cost savings. These changes are projected to decrease the model’s net spending for 2026 and improve outcomes for patients without disrupting their care.
  • The recently announced Long-term Enhanced ACO Design (LEAD) Model will launch in 2027 at the conclusion of ACO REACH. LEAD builds upon earlier accountable care work while appealing to a broader mix of health care providers, including those with specialized patient populations and those new to ACOs, such as smaller, independent or rural-based practices. LEAD will focus on better serving coordinated care for high-needs patients, such as those dually eligible for Medicare and Medicaid, and those who are homebound or home limited.

ACOs represent a critical component of CMS’ comprehensive strategy to increase value-based care for people with Medicare and Medicaid. This effort extends beyond ACOs to include initiatives like bundled payment models, managed care, and Medicare Advantage plans. Together, these create a system with accountability for both the quality and total cost of care to deliver better health outcomes at better costs for the American people.

CMS Accountable Care Organization Initiatives — Participation Highlights

  • For the 2026 performance year, CMS approved 134 applications for the Shared Savings Program, including 72 new ACOs and 62 renewing or reentering ACOs. This brings the total number of ACOs participating in the Shared Savings Program for Performance Year 2026 to 511, up from 476 ACOs participating in 2025. These Shared Savings Program ACOs, with more than 700,000 health care providers and organizations, will serve 12.6 million people with Traditional Medicare, a 12.3% increase from 2025 and the largest number ever served by the program.
  • The ACO REACH Model has 74 ACOs with 125,909 health care providers and organizations providing care to an estimated 1.7 million people with Traditional Medicare. This model has 614 Federally Qualified Health Centers, Rural Health Clinics, and Critical Access Hospitals participating in 2026. 
  • The Kidney Care Choices (KCC) Model includes 74 Kidney Contracting Entities (KCEs) which are accountable for the quality and care of their aligned people with Traditional Medicare. The KCC Model has 7,534 participating health care providers and organizations, serving 237,000 people with Traditional Medicare who have chronic kidney disease and End-Stage Renal Disease in 2026.
  • The ACO PC Flex Model includes 23 ACOs serving 359,720 people with Traditional Medicare and tests a new payment model for primary care within the Shared Savings Program. ACOs jointly participate in the model and the Shared Savings Program.

Additional Information

Shared Savings Program

ACO REACH Model 

KCC Model 

ACO PC Flex Model

LEAD Model  

 

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