How do I know if my doctor is part of an ACO?

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You can find out if your doctor is part of an Accountable Care Organization (ACO) by asking your doctor's office directly, looking for a written notice or posted sign in their office, or calling 1-800-MEDICARE.

Ways to Find Out

  • Ask your doctor: You can directly ask your healthcare provider or their staff during your next visit if they participate in a Medicare ACO.
  • Check the office: Doctors participating in an ACO are required to display a poster or sign in their office notifying patients.
  • Look for written notice: Your primary care provider will often give you a written letter or notice if they join an ACO.
  • Call Medicare: You can call Medicare at 1-800-MEDICARE (1-800-633-4227) for confirmation and general information. TTY users can call 1-877-486-2048.
  • Check your online account: If you have Original Medicare, you can log in to your official account on the Medicare website to see if you have been assigned to an ACO based on your primary care doctor.

Is my doctor in an ACO?

To find out if your doctor is in an Accountable Care Organization (ACO), look for a poster in their office or ask them directly during your next visit.

How to Check

  • Look for a notice: Participating doctors and healthcare providers must display a poster in their office notifying patients of their ACO involvement.
  • Ask your doctor: You can directly ask your doctor or healthcare provider if they participate in a Medicare ACO or private ACO.
  • Check official tools: You can search for your doctor or group practice on the Medicare Care Compare tool or check official public records like the CMS ACO Participants Data.
  • Call Medicare: If you have Original Medicare, call 1-800-MEDICARE (1-800-633-4227) to ask about your provider's participation and manage your data-sharing preferences.

What an ACO Means for You

  • It is not an insurance plan: An ACO does not change your coverage, benefits, or out-of-pocket costs.
  • You keep your freedom of choice: You can still see any doctor or hospital that accepts Medicare, even if they are outside the ACO.
  • Coordinated care: The goal is for your primary care doctor, specialists, and hospitals to share medical information safely to avoid repeat tests and improve your overall care.

What is the downside of an ACO?

The primary downside of an Accountable Care Organization (ACO) is the potential for downside financial risk and heavy administrative burdens if patient care costs exceed expected targets.

Financial and Administrative Disadvantages

  • Financial Penalties: Under two-sided risk models, if the ACO fails to lower overall healthcare spending below the assigned benchmark, providers must pay money back to the insurer or Medicare.
  • High Upfront Costs: Joining or setting up an ACO requires expensive investments in health information technology, electronic health records, data analytics dashboards, and care coordination staff.
  • Increased Bureaucracy: Providers often face extra reporting requirements, quality metrics tracking, and administrative red tape that can distract from direct patient care.

Operational and Clinical Challenges

  • Loss of Autonomy: Physicians may feel their clinical freedom is restricted by institutional guidelines, utilization reviews, or network-preferred referral patterns.
  • Complex Management: Aligning incentives, corporate cultures, and policies across large networks of independent doctors, specialists, and hospitals is difficult and prone to friction.
  • Data and Privacy Hurdles: Sharing extensive patient data across different provider systems creates technical barriers and privacy management challenges.

Can you opt out of an ACO?

You cannot opt out of being assigned to an Accountable Care Organization (ACO), but you can opt out of Medicare sharing your personal health and claims data with them by calling 1-800-MEDICARE.

How ACOs Affect You

  • Not an insurance plan: An ACO is a group of doctors working together, not a new health plan.
  • No provider limits: You keep your full Original Medicare rights and can see any doctor who accepts Medicare.
  • Automatic assignment: If your primary doctor joins an ACO, Medicare places you in it automatically for better care coordination.

How to Opt Out of Data Sharing

  • Call Medicare: Dial 1-800-MEDICARE (1-800-633-4227) to stop Medicare from sharing your personal medical data.
  • What stays shared: Even if you opt out, Medicare may still share basic, non-identifiable information to measure health quality.
  • Switch doctors: You can choose to see a doctor who is not part of an ACO at any time.

What makes someone an ACO provider?

A healthcare provider becomes an ACO (Accountable Care Organization) provider by voluntarily joining a coordinated network of doctors, hospitals, and other clinicians who sign an agreement to take joint responsibility for the quality, cost, and patient experience of care for a defined group of patients.

What Qualifies as an ACO Provider?

  • Licensed Professionals: Individual practitioners like primary care physicians, specialists, nurse practitioners, and physician assistants.
  • Facilities and Institutions: Hospitals, skilled nursing facilities, critical access hospitals, rural health clinics, and federally qualified health centers.
  • Good Standing: Any Medicare-enrolled provider or supplier who meets program standards and wishes to participate in value-based care.

How the Process Works

  • Voluntary Agreement: Providers choose to partner and align with an Accountable Care Organization structure rather than acting entirely isolated.
  • Shared Accountability: Providers agree to meet specific quality performance standards and manage overall healthcare spending for assigned traditional fee-for-service beneficiaries.
  • Shared Savings: In exchange for meeting efficiency and care goals, participating providers can earn a portion of the financial savings they generate for the healthcare system.

Doctors ACO Explained

9 related questions found

Are ACOs a good thing?

Accountable Care Organizations (ACOs) can be a good thing because they help coordinate patient care, improve medical outcomes, and lower unnecessary healthcare costs.

The Benefits of ACOs

  • Better Care Coordination: Doctors and hospitals share information so patients get seamless care without repeating tests.
  • Shared Savings: When an ACO lowers costs while keeping quality high, it can earn financial bonuses from CMS.
  • Focus on Prevention: Patients get more preventive services like annual wellness visits and chronic disease management.

The Drawbacks and Risks

  • Financial Risk: Some models require providers to take on downside risk, meaning they may lose money if costs go up.
  • Administrative Burden: Practices face extra reporting, data tracking, and IT expenses.
  • Mixed Results: Critics point out that not all ACO experiments achieve large savings, and smaller practices may struggle with the required infrastructure.

What are red flags for a doctor?

Red flags for a doctor include poor communication, dismissing your symptoms, and rushing through appointments without a proper investigation.

Communication and Behavior

  • Interrupting and dismissing: A doctor who constantly cuts you off or writes off your concerns without listening.
  • Medical gaslighting: Blaming your symptoms entirely on stress, age, or weight without running basic tests.
  • Rushed visits: Spending only a few minutes in the room and failing to answer your questions.
  • Condescending attitude: Acting rude, arrogant, or defensive when you ask for clarification or a second opinion.

Care and Competence

  • Skipping diagnostics: Refusing to order standard follow-up tests or imaging when your symptoms persist.
  • Disorganization: Frequently losing your test results, mixing up charts, or showing a lack of basic preparation for your visit.
  • Poor coordination: Failing to communicate or share vital records with your other specialists or care team.

For more detailed insights on when it is time to move on, read this guide on U.S. News or review these 7 Signs of a Bad Doctor.

Do ACOs only serve Medicare patients?

No, Accountable Care Organizations (ACOs) do not only serve Medicare patients.

While the term "ACO" is most commonly associated with Medicare Accountable Care Organizations through government programs like the Medicare Shared Savings Program, many healthcare provider groups also enter into commercial ACO contracts with private health insurers, as well as arrangements with Medicaid.

How Patient Populations Work in ACOs

  • Medicare ACOs: Focus specifically on coordinating care and managing costs for assigned Traditional Medicare beneficiaries. However, the individual doctors and clinics inside a Medicare ACO still treat non-Medicare patients every day.
  • Commercial ACOs: Formed when provider networks partner with private insurance companies to apply the same value-based care and cost-saving coordination to privately insured (commercial) patients.
  • Dual Focus Practices: Many medical groups participate in multiple value-based programs at once, meaning the same clinic may care for Medicare, Medicaid, and commercial patients under different coordinated frameworks.

Is ACO reach ending in 2026?

Yes, the ACO REACH Model is scheduled to end on December 31, 2026, marking the conclusion of its four-year performance period.

Transition to the LEAD Model

  • Replacement: The Centers for Medicare & Medicaid Services (CMS) Innovation Center is launching the Long-term Enhanced ACO Design (LEAD) Model to take its place.
  • Timeline: LEAD begins on January 1, 2027, and is structured as a 10-year initiative running through 2036.
  • Focus: The new model aims to support smaller independent providers, rural practices, and organizations serving complex or dually eligible beneficiaries.

Key Considerations for ACOs

  • Final Year Adjustments: Performance Year 2026 brings updated risk score caps and adjusted regional benchmark weightings under CMS Guidelines.
  • Alternative Pathways: Organizations not transitioning to LEAD are evaluating shifts to the permanent Medicare Shared Savings Program (MSSP) or other commercial options.

How are patients assigned to an ACO?

Patients are assigned to an Accountable Care Organization (ACO)—a process also called attribution—based on where they receive the plurality (the most) of their primary care services, rather than by signing up or enrolling.

How Assignment Works

  • No Enrollment Needed: Patients do not choose or sign up for an ACO. The assignment happens automatically behind the scenes using medical billing and claims data.
  • Plurality of Care: A patient is assigned to the ACO where they received the largest share of their primary care services (such as routine office visits or wellness exams) from participating doctors or providers.
  • Step-Wise Process (Medicare):
    1. Step 1: Looks at whether the patient saw primary care physicians (like internal medicine or family practice) within the ACO and assigns them based on who provided the most services.
    2. Step 2: If the patient did not see a primary care physician, Medicare looks at nurse practitioners, physician assistants, clinical nurse specialists, or specialist visits to determine assignment.
  • Timing of Assignment:
    • Prospective Assignment: Patients are assigned at the start of the year based on their prior year's medical history.
    • Retrospective Assignment: Patients are assigned at the end of the performance year based on where they actually received their care during that year.

Patient Choice and Freedom

  • Free Choice Maintained: Patients assigned to an ACO are never "locked in". They keep their original coverage (such as traditional Fee-for-Service Medicare) and can visit any doctor or specialist they want, even if that provider is outside the ACO.
  • Opting Out: Beneficiaries can request to opt out of having their data shared or used in ACO performance calculations, though they still receive care as usual. You can learn more about how CMS Assigns Beneficiaries to ACOs through official program guidelines.