CMS Open Payments · Rate Limits

Open Payments Rate Limits

CMS Open Payments does not publish fixed numeric per-key rate limits, because the API requires no key or account. Practical throughput is governed by the page-size / limit parameters on each endpoint (search caps page-size at 100; datastore queries default to a 500-row limit and page via limit and offset) and by fair-use expectations for a shared public federal service. Very large pulls are better served by the CSV/JSON download endpoints or the bulk dataset files than by deep pagination of the query API.

Open Payments Rate Limits is the machine-readable rate-limit profile for CMS Open Payments on the APIs.io network, conforming to the API Commons Rate Limits specification.

It captures 3 rate-limit definitions, measuring rows, results, and requests.

The profile also includes 3 backoff/retry policies defined and response codes documented for throttled.

Tagged areas include Government Data, Healthcare, Open Data, Rate Limiting, and Quotas.

3 Limits Throttle: 429
Government DataHealthcareOpen DataRate LimitingQuotas

Limits

Datastore Query Row Limit request
rows
500 default per request
Set limit and offset to page through results; count in the response gives the full match size.
Search Page Size request
results
100 max per page
The /search endpoint caps page-size at 100; use page to paginate.
Public Request Rate global
requests
not published
No fixed per-client request-rate limit is documented; fair use applies to the shared federal service.

Policies

Fair Use
A shared public federal API. Prefer bulk download endpoints for whole-dataset extracts rather than deep pagination.
Backoff Strategy
On 429 or 503 responses, back off exponentially with jitter before retrying.
Pagination
Use limit and offset on datastore queries and page / page-size on search and metastore listings.

Sources

Work with this as data

Every rate limit here is available over the APIs.io API and to AI agents over MCP.

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Tools for rate limits

4 MCP tools reach this
  • find_rate_limitsBrowse and filter every rate limit in the catalog.
  • apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
  • resolveTurn a domain, URL or GitHub org into the provider it belongs to.
  • find_cohortsEvery scored population of providers in the catalog.
All 92 tools

Call it yourself

curl for this page
This rate limit 
curl "https://apis.io/api/v1/rate-limits/open-payments-rate-limits"
All rate limits 
curl "https://apis.io/api/v1/rate-limits?limit=25"

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