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CMSProvider performanceUpdated 2026-06-14

Medicare Shared Savings Program ACO Participants

Medicare Shared Savings Program accountable care organization participants — ACO legal business names and participation by performance year. Source: Centers for Medicare & Medicaid Services · 2026-06-14

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15,329
ACO participant records
As of 2026-06-14
CMS · 2026-06-14
2025
Temporal coverage
Refreshed annual
CMS · 2026-06-14
Organization
FHIR resource
FHIR R4 · cms-mssp-aco/v1
Fonteum methodology

FHIR Organization · Sample record

What a record looks like in the API response.

Sample record
{
  "resourceType": "Organization",
  "id": "mssp-aco-example",
  "_source": "cms-mssp-aco",
  "_methodology": "cms-mssp-aco/v1",
  "name": "Example ACO Participant LLC",
  "extension": [{ "url": "performanceYear", "valueInteger": 2025 }]
}

Every record carries _source, _methodology, a snapshot date, and a confidence tier. All fourteen provenance fields survive export and API delivery.

cURL
curl -H "Authorization: Bearer $FONTEUM_KEY" \
  "https://api.fonteum.com/fhir/r4/Organization?_source=cms-mssp-aco" \
  | jq '._source, ._methodology, .meta.tag'

Dataset facts

Dataset facts for Medicare Shared Savings Program ACO Participants
FieldValue
AgencyCenters for Medicare & Medicaid ServicesCMS · 2026-06-14
CategoryProvider performance
Records15,329 ACO participant recordsCMS · 2026-06-14
Temporal coverage2025
Refresh cadenceAnnual
Freshness SLAWithin 7 days of annual CMS release
Last synced2026-06-14Updated 2026-06-14
FHIR resourceOrganization
Methodologycms-mssp-aco/v1
MeasuredACO id, participant legal business name, and performance year per participant
Upstream sourcedata.cms.gov →

Get access

How to reach this dataset.

API access is operator-approved during the pilot. Reviewed within one business day. No charge during the pilot period.

Request access →Download CMS CSV →View methodology

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Citations

  1. Centers for Medicare & Medicaid Services — Medicare Shared Savings Program ACO Participants (upstream source)
  2. Fonteum methodology (cms-mssp-aco/v1)
  3. Editorial & licensing policy
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Reviewed by Jennifer Montecillo, MD, medical reviewer. Non-practicing medical reviewer.

© 2026 Fonteum LLC. All rights reserved.

The U.S. healthcare graph AI can cite — every fact carries its source.

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