Program Data

The Shared Savings Program makes data on Accountable Care Organizations (ACOs) publicly available through different sources. Find the most recent data on this webpage and For a complete list of publicly available data, reference Publicly Available Data Sources and ACO Performance Data maintained by CMS (PDF).

ACO Participation and Performance Data

Program Fast Facts

Provides summary information about the Shared Savings Program as of January 1, 2020, including:

  • Historical program information (including program size, quality, and shared savings)
  • ACO information (including characteristics, composition, and participation information)
  • ACO assigned beneficiary population

2020 Shared Savings Program Fast Facts (PDF)

Previous Program Fast Facts are available in the Fast Facts Archives (ZIP)


Displays an interactive map of the U.S. showing (pinpoint) locations of Shared Savings Program ACOs and select details including:

  • ACO service area
  • ACO Public Contact information
  • ACO public reporting website

2020 Shared Savings Program ACO Map

List of ACOs

Provides organizational information about ACOs including:

  • Name
  • Start date
  • Track
  • Address
  • Service area
  • Public reporting website
  • Executive Contact information
  • Public Contact information

2020 Shared Savings Program ACOs 

List of ACO Participants

Shows a listing of ACO participants by ACO name.

2020 Shared Savings Program ACO Participants

List of Skilled Nursing Facility (SNF) Affiliates

Shows a listing of ACO SNF affiliates by ACO name.

2020 Shared Savings Program SNF Affiliates

ACO ID Crosswalk

This data set includes the ACO ID (Axxxx).  Prior to July 2019, the data sets included an encrypted ACO ID (Axxxxx). Research Identifiable Files (RIFs) and Public Use Files (PUFs) created prior to July 2019 identify ACOs using the encrypted ACO ID.  RIFs and PUFs created in July 2019 and late will identify ACOs using their un-encrypted ACO ID. To facilitate comparisons between data sets created before July 2019 and after July 2019, we are making a crosswalk available.

ACO ID Crosswalk (XLSX)     

ACO Public Use File

To address the increasing number of requests for Shared Savings Program ACO data and to inform those interested in the policies finalized in the Shared Savings Program, the Centers for Medicare and Medicaid Services (CMS) has created standard analytical files providing publicly available information.

  • Shared Savings Program ACO PUF: Provides financial and quality performance data for each de-identified ACO, by performance year, including the following:
    • Overall quality score
    • Final sharing rate
    • Minimum savings rate (MSR)
    • Minimum loss rate (MLR)
    • Benchmark
    • Assigned beneficiary demographic characteristics and provider/supplier composition
  • Shared Savings Program Benchmark PUFs: Standard analytical files of the regional fee-for-service (FFS) expenditures used to calculate the historical benchmarks for ACOs and the annual updates to these benchmarks (as applicable based on the ACO's agreement period start date). For each calendar year, CMS will release two PUFs: (1) Aggregate Expenditure and Risk Score Data on Assignable Beneficiaries by County PUF and (2) Number of ACO Assigned Beneficiaries by County.

Research Identifiable Files

Certain identifiable performance year data is available through ResDAC for a fee to researchers who obtain an appropriate Data Use Agreement (DUA).

  • Beneficiary-Level RIF: Beneficiary-identifiable data for every beneficiary assigned to a Shared Savings Program ACO, including: ACO identifier, preliminary assignment, quarter of assignment, final assignment, unique beneficiary identifier, date of birth/death, gender, race, reason for Medicare eligibility, dual status, Part D enrollment status, and monthly eligibility flag.
  • Provider-Level RIF: Provider-identifiable data for institutional and individual providers who participated in a Shared Savings Program ACO during the performance year, including: ACO name and start date; provider identifiers; and provider characteristics (facility type – institutions; practice type/specialty – individuals, count primarily served).


For additional information on Shared Savings Program ACOs, please visit

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Page Last Modified:
03/10/2020 02:20 PM