Particle Health vs Zus Health (2026)
Both retrieve patient records from the national networks and reach about 320 million patients, and they differ in what they hand back. Particle is an interface: a single API over CommonWell, Carequality, eHealth Exchange and state exchanges, with Snapshot summaries, Signal admission alerts and curated datasets on top. Zus is a platform: it assembles one longitudinal record per patient with its own patient index, shares customers' data back to the networks, and embeds that record inside athenahealth, Elation, Canvas and Healthie. Both now sell to value based care organizations. An interface is easier to leave; a shared platform is harder to leave and gives more in return.
- One API over the three national networks and state exchanges, returning FHIR, C-CDA or tabular data.
- Signal's nationwide admission and discharge alerts are sold for readmission reduction, and its security posture names HITRUST and SOC 2.
- A free developer sandbox, with Snapshot summaries and curated datasets available on top of retrieval.
- A single deduplicated record per patient through its own universal patient index, shared back to the networks.
- Embedded views inside athenahealth, Elation, Canvas and Healthie put the record where clinicians already work.
- Its patient summary cites a source for every clinical statement, and a risk adjustment add-on suggests HCC codes for value based care organizations.
This comparison is published by AI Health Index, an independent research platform that compares healthcare AI vendors objectively. Particle Health and Zus Health are each graded against the same capability taxonomy, from each vendor's own public materials and the regulatory record, under the AI Health Index verification standard. No vendor pays for placement, and no vendor has reviewed this page. How this evidence is graded
Plain facts
| Fact | Particle Health | Zus Health |
|---|---|---|
| Primary category | Healthcare Administrative Automation | Healthcare Administrative Automation |
| Founded | Not recorded | 2020 |
| Headquarters | New York, New York | Boston, Massachusetts, United States |
| Website | particlehealth.com | zushealth.com |
Side by Side
Select any grade to read the note behind it.
Product updates
The latest logged changes from each vendor, newest first, each linked to its source.
Zus Health
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Security / compliance
Zus added a managed role, Builder Data Integration, for App Clients that get access tokens on behalf of users, such as EHR integrations or Zus apps embedded in a customer's interface, through the proxy token endpoint.
Source -
Security / compliance
Zus refreshed the code sets behind its automatic tagging of specially regulated records against current VSAC value sets.
Source
Each vendor in one paragraph
Written to be quoted whole. Each paragraph opens the AI Health Index profile of the vendor: what the product is, who buys it and what it does.
Particle Health sells access to patients' medical records through a single API. It queries CommonWell, Carequality, eHealth Exchange and state HIEs, with ADT feeds and pharmacy fill data, returning FHIR R4, C-CDA or its own tabular format, and reports 320 million patients across more than 70,000 organizations, finding on average 90 percent of patients nationally.
Source: AI Health Index, September 2026
Zus Health assembles a longitudinal patient record from national data networks and delivers it to care teams, analysts and developers. The Zus Aggregated Profile queries CommonWell and Carequality for medical history, adds pharmacy fill data, admission and discharge feeds and lab results, matches records to one person through a proprietary universal patient index, deduplicates and normalizes everything to FHIR, and shares a customer's contributed data back to the networks.
Source: AI Health Index, September 2026
Questions buyers ask
How do Particle Health and Zus Health work with the EHR?
For Particle Health, a single bidirectional RESTful API returns FHIR R4 or C-CDA data from CommonWell, Carequality, eHealth Exchange and state HIEs, plus ADT feeds and pharmacy fill data, reaching what the company reports as more than 70,000 organizations and 320 million patients and finding on average 90 percent of patients nationally.
With Zus Health, the Zus Aggregated Profile is available inside athenahealth, Elation Health, Canvas Medical and Healthie, each with its own integration page and clinical guide entry, and through a standalone app, embeddable components, REST and GraphQL APIs, webhooks and analytics data marts. From the AI Health Index, drawn from each vendor's own published materials and the regulatory record, verified September 23, 2026. No vendor pays for placement.
How are Particle Health and Zus Health priced and sold?
In Particle Health's case, the pricing unit is not stated.
For Zus Health, the product is sold through contact, with a public sandbox for developers, and the documentation describes data subscription packages that patients are enrolled in and one-time queries; the release note for the Generated Patient Summary says it is free for existing customers. The pricing unit is not stated, and it could be per enrolled patient, per query, per data package or a platform fee. From the AI Health Index, drawn from each vendor's own published materials and the regulatory record, verified September 23, 2026. No vendor pays for placement.
Which settings and specialties do Particle Health and Zus Health cover?
With Particle Health, the company also sells the same data to value based care organizations and payers for care gap closure and HEDIS, MIPS and Star Ratings reporting, with Signal alerts sold for readmission reduction.
In Zus Health's case, the platform serves care teams through its app and embedded views, population health analysts through data marts, and developers through APIs and webhooks, for new-patient intake without an intake form, visit preparation, medication adherence alerts, admission and discharge detection and population health. From the AI Health Index, drawn from each vendor's own published materials and the regulatory record, verified September 23, 2026. No vendor pays for placement.
What evidence is published for Particle Health and Zus Health?
For Particle Health, the home page quotes One Medical on gathering external health data before a first visit, xCures on growth and scalability, and Cureatr on pharmacist recommendations from discharge summaries, and the company reports 320 million patients, more than 70,000 organizations and 90 percent of patients found on average. No clinical evidence applies, since the product retrieves rather than decides.
With Zus Health, the denominators are patients reviewed and suggestions made, but neither count is given, the three pilots are pooled with no period, and coder acceptance measures agreement with coders, not whether the codes survive a risk adjustment audit. From the AI Health Index, drawn from each vendor's own published materials and the regulatory record, verified September 23, 2026. No vendor pays for placement.
Related comparisons
Other published head to head assessments involving these vendors or their closest peers. The full set for this category is on the Clinical Summarization & Chart Review page.
Both make universal claims the evidence does not support. Particle says its matching guarantees every retrieved record belongs to the intended patient, while its own blog discusses identity failures. Zus's blog says its summary never misses the big picture, while its release note says it may not capture all relevant details.
Particle names HITRUST and SOC 2; Zus names SOC 2 Type 2 but not where it runs. Neither publishes a price. Ask both how permitted use is enforced for your customer category.