Omnisend · Rate Limits

Omnisend Rate Limits

Published rate limits for the Omnisend API at version 2026-03-15, read from the provider's own rate-limit reference page and cross-checked against the per-operation "Rate Limiting" notes in llms.txt. Limits are enforced at the API gateway PER BRAND on a sliding window — every request made on behalf of the same brand counts toward the same budget regardless of which API key, OAuth token or integration sent it. The runtime signal is the finding: Omnisend publishes NO rate-limit response headers at all.

Omnisend Rate Limits is the machine-readable rate-limit profile for Omnisend on the APIs.io network, in the API Commons Rate Limits shape.

It captures 7 rate-limit definitions.

Limit state is signalled in the rate_limit_headers_published, x_ratelimit, ratelimit, and retry_after response headers, and an exhausted limit returns HTTP 429.

The profile also includes 5 backoff/retry policies defined and response codes documented for throttled, quotaExceeded, and conflict.

Tagged areas include Rate Limiting, Quotas, and Email Marketing.

7 Limits Exhausted: HTTP 429 Quota: 429 rate_limit_headers_publishedx_ratelimitratelimitretry_after
Transcribed from the provider's documentation on 2026-08-13 — api-docs.omnisend.com/reference/rate-limit-timeouts-errors.
View Source
Rate LimitingQuotasEmail Marketing

Limits

all endpoints (default)
/segments
/segments
The strictest per-minute limit Omnisend publishes. Segment authoring must be batched, not looped.
/contacts/tags
Bulk tag add/remove. Asynchronous — the tag may not be visible on the next read.
/email-templates/{id}/render
/email-content/{id}/render
/analytics/reports/analytics/statistics
The only endpoints with a daily quota. Up to 4 queries per request, so budget query batching accordingly.

Policies

Sliding window
The counter tracks requests over the last minute (or 24 hours for daily quotas) rather than resetting at fixed intervals, so bursts at window boundaries are not possible.
Per-brand aggregation
All API keys, OAuth tokens and integrations acting for one brand share a single budget. A partner app and the merchant's own scripts throttle each other.
429 handling
Read `retryAfter` from the RFC 9457 body when present; otherwise back off exponentially. There is no header to read.
Prefer batches
Omnisend recommends POST /batches explicitly as the way to avoid hitting rate limits on bulk work.
Building-state segments
A segment in `building` state returns 409 Conflict for update and delete — a state error, not a rate-limit error.

Sources

Work with this as data

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

MCP server

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https://apis.io/mcp

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/omnisend-rate-limits"
All rate limits 
curl "https://apis.io/api/v1/rate-limits?limit=25"

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