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, conforming to the API Commons Rate Limits specification.

It captures 7 rate-limit definitions.

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 Throttle: 429 Quota: 429
Rate LimitingQuotasEmail Marketing

Limits

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