---
title: "Integrations - Lettr"
url: "https://docs.unified.to/integrations/lettr"
description: "Build Lettr integrations faster with our Unified API — Marketing data, API key, real-time sync."
date: "2026-11-12T22:56:59.465Z"
updated: "2026-11-12T22:56:59.465Z"
---

# Lettr integration

> What this integration supports through the Unified.to API, by object. Live data: `GET https://api.unified.to/unified/integration?type=lettr` with your workspace API key (or Core MCP `list_unified_integrations` with `type: "lettr"`). All integrations: https://docs.unified.to/integrations.md

## Overview

- **Type:** `lettr`
- **Categories:** [Marketing](https://docs.unified.to/martech/overview.md), [Messaging](https://docs.unified.to/messaging/overview.md), [Passthrough](https://docs.unified.to/passthrough/overview.md)
- **Website:** https://lettr.com
- **Vendor API docs:** https://docs.lettr.com/api-reference/introduction
- **Launched:** 2026-11-12

## How end users connect

- **API key** entered by the end user: `API Key`
    - Create an API key in the Lettr dashboard at [app.lettr.com](https://app.lettr.com) under API Keys. Give it full access (or the audience:read/write, campaigns:read/write and emails:read scopes plus sending) for every object to work.

## Supported objects

| Object | Methods | Webhooks |
| --- | --- | --- |
| [martech_campaign](#martech_campaign) | list, get, create | none |
| [martech_list](#martech_list) | list, get, create, update, remove | none |
| [martech_member](#martech_member) | list, get, create, update, remove | none |
| [martech_report](#martech_report) | list | none |
| [messaging_message](#messaging_message) | get, create | none |
| [passthrough](#passthrough) | none | none |

Values below come from the integration's support data. "Required list filters" must be sent on list calls; "Required on create" fields must be sent when creating. Webhook events are `native` (pushed by the vendor) or `virtual` (polled by Unified.to). Anything not listed is not supported; an unsupported method returns `501`.

### martech_campaign

- **Methods:** `list`, `get`, `create`
- **Webhooks:** none
- **List filters:** `list_limit`, `list_offset`
- **Readable fields:** `created_at`, `from_email`, `from_name`, `id`, `list_ids`, `name`, `reply_to_email`, `send_at`, `status`, `subject_line`
- **Writable fields:** `from_email`, `from_name`, `list_ids`, `name`, `reply_to_email`, `subject_line`
- **Vendor objects:** `campaign`
- **Model:** https://docs.unified.to/martech/campaign/model.md

### martech_list

- **Methods:** `list`, `get`, `create`, `update`, `remove`
- **Webhooks:** none
- **List filters:** `list_limit`, `list_offset`
- **Readable fields:** `id`, `name`
- **Writable fields:** none
- **Required on create:** `name`
- **Vendor objects:** `audience_list`
- **Model:** https://docs.unified.to/martech/list/model.md

### martech_member

- **Methods:** `list`, `get`, `create`, `update`, `remove`
- **Webhooks:** none
- **List filters:** `list_limit`, `list_list_id`, `list_offset`, `list_query`
- **Readable fields:** `created_at`, `emails`, `id`, `list_ids`, `metadata`, `status`
- **Writable fields:** `list_ids`, `metadata`, `status`
- **Required on create:** `emails`
- **Vendor objects:** `audience_contact`
- **Model:** https://docs.unified.to/martech/member/model.md

### martech_report

- **Methods:** `list`
- **Webhooks:** none
- **List filters:** `list_limit`, `list_offset`
- **Readable fields:** `abuse_reports`, `campaign_id`, `click_rate`, `clicks_total`, `emails_sent`, `id`, `open_rate`, `opens_total`, `sent_at`, `unique_clicks`, `unique_opens`, `unsubscribed`
- **Writable fields:** none
- **Vendor objects:** `campaign`
- **Model:** https://docs.unified.to/martech/report/model.md

### messaging_message

- **Methods:** `get`, `create`
- **Webhooks:** none
- **Readable fields:** `author_member`, `created_at`, `destination_members`, `hidden_members`, `id`, `mentioned_members`, `message`, `message_html`, `subject`
- **Writable fields:** `hidden_members`, `mentioned_members`, `message`, `message_html`, `subject`
- **Required on create:** `author_member`, `destination_members`
- **Vendor objects:** `email`
- **Model:** https://docs.unified.to/messaging/message/model.md

### passthrough

- **Methods:** none
- **Webhooks:** none
- **Readable fields:** none
- **Writable fields:** none