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Omnisend

Omnisend Contacts API

The Contacts API from Omnisend — 7 operation(s) for contacts. Version 2026-03-15, harvested from Omnisend's published contract.

Documentation Provider Profile APIs.io OpenAPI GitHub

Omnisend Contacts API is one of 15 APIs that Omnisend publishes on the APIs.io network, described by a machine-readable OpenAPI specification.

This API exposes 2 JSON Schema definitions.

Tagged areas include Contacts. The published artifact set on APIs.io includes an OpenAPI specification, API documentation, an API reference, authentication docs, a JSON-LD context, and 2 JSON Schemas.

This API exposes 7 operations across 3 paths, and defines 19 schemas. It is described by OpenAPI 3.0.0, at version 2026.

Requests are made against a single base URL, https://api.omnisend.com/api.

7 operations 3 paths 19 schemas 1 DELETE2 GET2 PATCH2 POST

Metadata

The identity and technical contract details declared by the specification.

Specification
OpenAPI 3.0.0
API Version
2026
Base URL
https://api.omnisend.com/api
Authentication
API Key, OAuth 2.0
Resource Areas
1

Authentication & Security 2

Omnisend Contacts API declares 2 security schemes for authenticating requests. An API key is passed in the header as Authorization (ApiKeyAuth). It supports OAuth 2.0 (Bearer) using the clientCredentials flow, exposing 2 scopes.

  • ApiKeyAuth — API Key authentication. Value format: 'Omnisend-API-Key {api-key}'

Paths & Operations 7

Across 3 paths, the API surfaces 7 operations — 1 DELETE, 2 GET, 2 PATCH, 2 POST. Each is listed below with its method, path, parameters, and response codes.

Contacts 7
GET
/contacts
List contacts
12 params → 200400401403410429500
PATCH
/contacts
Update contact by email
2 params body → 200400401403404409410429
POST
/contacts
Create or update existing contact
1 param body → 200201400401403410429500
GET
/contacts/{id}
Get contact
2 params → 200400401403404410429500
PATCH
/contacts/{id}
Update contact by ID
2 params body → 200400401403404409410429
DELETE
/contacts/tags
Batch remove tags
1 param body → 202400401403410429500
POST
/contacts/tags
Batch add tags
1 param body → 202400401403410429500

Schemas 19

The contract defines 19 schemas that model the data the API accepts and returns. The most detailed are ContactResponse (23 properties), ContactRequest (14 properties), RateLimitProblem (6 properties), ValidationProblem (6 properties). Each schema is shown below with its type and property counts.

AddTagsRequest
object
Payload for batch adding tags to contacts.
5 properties 1 required
Channel
object
Channel subscription status.
2 properties
Consent
object
Consent record for a contact channel.
5 properties
ContactChannelRequest
object
Channel subscription details.
2 properties 1 required
ContactConsentRequest
object
Consent record.
4 properties
ContactIdentifierRequest
object
A unique contact identifier (email or phone). For phone: provide the full number with country code prefix in E.164 format (e.g. +1234567890).
6 properties 2 required
ContactRequest
object
Payload for creating or updating a contact.
14 properties
ContactResponse
object
Contact resource representation.
23 properties
ContactStatus
object
Contact status per channel.
3 properties
CursorsResponse
object
Cursor pointers for paginating forward and backward through results
2 properties
FieldError
object
A single field validation failure within a validation error response.
3 properties
Identifier
object
Unique contact identifier (email or phone).
3 properties
ListContactsResponse
object
Paginated list of contacts.
2 properties
OptIn
object
Contact opt-in record.
2 properties
PagingResponse
object
Cursor-based pagination metadata
3 properties
Problem
object
Standard error response returned by all API endpoints on failure.
5 properties
RateLimitProblem
object
Error response returned when the rate limit is exceeded. Use the retryAfter value to know when it is safe to retry the request.
6 properties
RemoveTagsRequest
object
Payload for batch removing tags from contacts.
5 properties 1 required
ValidationProblem
object
Error response returned when the request contains invalid input. The errors array lists every field that failed validation.
6 properties

Specification

The full machine-readable OpenAPI contract behind this narrative.

Source

omnisend-contacts-api-openapi.yml Raw ↑

Other APIs Omnisend publishes across the network.

Omnisend Analytics API
AE Profile APIs.io
Omnisend Batches API
AE Profile APIs.io
Omnisend Brands API
AE Profile APIs.io
Omnisend Campaigns API
AE Profile APIs.io
Omnisend EmailContent API
AE Profile APIs.io
Omnisend EmailTemplates API
AE Profile APIs.io
Omnisend EmailUniversalLayouts API
AE Profile APIs.io
Omnisend Events API
AE Profile APIs.io
Omnisend Images API
AE Profile APIs.io
Omnisend ProductCategories API
AE Profile APIs.io
Omnisend Products API
AE Profile APIs.io
Omnisend Segments API
AE Profile APIs.io
#Contacts
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API Details
ID
omnisend:omnisend-contacts-api
Base URL
https://api.omnisend.com/api
Docs
https://api-docs.omnisend.com/reference/overview
Provider
Omnisend
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