Intro

Endpoint: https://api.omnisend.com/api/events

Guide: How to send events using Events API

Send customer events to Omnisend to track behavior and trigger automations. Events can be recommended (predefined e-commerce actions) or custom (user-defined for flexible tracking).

Event Types

Type	Description
recommended	Predefined events with specific names and properties (e.g., "placed order", "added product to cart"). Enable pre-built automations, reporting, and segment templates.
custom	User-defined events with arbitrary names and properties. Used for custom automation triggers, segmentation rules, and contact profile tracking.

For a full list of recommended events and their schemas, see the Events Overview.

Version and Origin

Every event requires origin and recommended events require eventVersion. Incorrect values can cause issues with automations, segmentation, and reporting.

Field	Recommended events	Custom events
eventVersion	Predefined per event — see each event's documentation	Not required, can be omitted
origin	`api` for custom stores, app name for 3rd-party apps	`api` for custom stores, app name for 3rd-party apps

Note: If you are an e-commerce platform building an integration, contact Omnisend for origin guidance.

Event Deduplication

To avoid processing duplicate events, include both eventID and eventTime in the payload. Events with the same eventID and eventTime are processed only once.

Warning: Deduplication works only for historical events. It does not apply to real-time events used for automations.

Example: Send a custom event

curl --request POST \
     --url https://api.omnisend.com/api/events \
     --header 'Authorization: Omnisend-API-Key YOUR_API_KEY' \
     --header 'Omnisend-Version: 2026-03-15' \
     --header 'Content-Type: application/json' \
     --data '{
  "eventName": "my custom event",
  "origin": "api",
  "contact": {
    "email": "jane.doe@example.com"
  },
  "properties": {
    "customField": "value"
  }
}'

Example: Send a recommended event

curl --request POST \
     --url https://api.omnisend.com/api/events \
     --header 'Authorization: Omnisend-API-Key YOUR_API_KEY' \
     --header 'Omnisend-Version: 2026-03-15' \
     --header 'Content-Type: application/json' \
     --data '{
  "eventName": "added product to cart",
  "origin": "api",
  "eventVersion": "",
  "eventID": "f3f61bc6-07b8-4645-92d8-189d882dbcb1",
  "eventTime": "2024-07-01T12:00:00Z",
  "contact": {
    "email": "jane.doe@example.com"
  },
  "properties": {
    "abandonedCheckoutURL": "https://example.com/checkout",
    "cartID": "cart-123",
    "currency": "USD",
    "lineItems": [
      {
        "productID": "prod-1",
        "productTitle": "Running Shoes",
        "productPrice": 79.99,
        "productQuantity": 1,
        "productURL": "https://example.com/products/running-shoes",
        "productImageURL": "https://example.com/images/running-shoes.jpg"
      }
    ],
    "value": 79.99
  }
}'

For the full list of properties for each recommended event, see the individual event pages linked from the Events Overview.

See Also

Events Overview
How to send custom events to trigger custom automations
Errors & responses