How can Letterhead integrate with other software?

Letterhead offers multiple ways to integrate with other tools. This article breaks down the available options and the level of technical skill each one may require.

The integration options available with Letterhead are:

Zapier
API
Webhooks

Zapier

This is the no-code option to integrate Letterhead with other applications.

To use Zapier to integrate, you will need a Zapier account, which you can sign up for free or choose any of the paid plans.

Also, the application you want to connect to needs to integrate with Zapier already, and You can check that here.

Zapier is a no-code automation platform that connects different apps and services to automate workflows. It allows users to create automated sequences, called "Zaps", that trigger actions based on specific events in one app and execute tasks in another—without requiring any coding.

How Zapier Works

Trigger – An event in one app starts the workflow (e.g., a newsletter goes out from Letterhead).
Action – Zapier performs an action in another app based on the trigger (e.g., sends a Slack letting your team know it went out).
Multi-Step Zaps – You can chain multiple actions together (e.g., sending a Slack notification after saving the file).

Key Features

Supports 6,000+ apps, including Letterhead, Slack, Salesforce, Google Workspace, etc.
No-code builder for setting up automations
Conditional logic (if/then logic)
Scheduled and real-time automations
Multi-step workflows for complex processes

Use Cases

Add, update, or remove subscribers
Add an article to Curations
Send a Slack message when a newsletter is published

You can refer to this article to connect Letterhead to your Zapier account.

API

API stands for Application Programming Interface.

APIs allow developers to sync data between multiple platforms and can facilitate communication among the various services in web applications. API integration is what does the work when, for example, you enter a new contact in your CRM, and it auto-populates to Letterhead as well.

This option requires a developer to build it using our API documentation because leveraging APIs requires proficiency in one or more programming languages that are commonly used for creating APIs. They need to be familiar with the syntax, libraries, frameworks, and tools that are relevant for API development. It is the most versatile of the options we offer.

To get started, you'll need an API key from your Letterhead account. Learn how to generate your API key →

Use Cases

Add, update, or remove subscribers
Add articles to your Curations library
Schedule or send a letter based on an action in another application

Webhooks

Webhooks are automated messages sent from applications, whenever a specific event occurs, and can be used to trigger an event in another app. It is a type of event-driven API. APIs are manual, they need to be asked to pull or modify data.

Webhooks automatically send data in response to a specific event without any request from another software. Webhooks are a subset of APIs and are, therefore, far more limited than APIs—they can only send information.

In other words, when an event, such as a newsletter going out, happens in Letterhead, it lets the other application know, so that a different action is triggered in the connected application.

This option may require a developer that understands how webhooks work and can complete the rest of the actions in the other application; however, if you use another third-party integration tool similar to Zapier that Letterhead is not integrated with yet, like Workato or Integrately, you may use webhooks in Letterhead to trigger actions in a separate application without having the technical expertise, using their webhook action options.

You can refer to this article on how to use webhooks with Letterhead.

Use Cases

Updating user subscription status in your customer relationship management (CRM) system when a user unsubscribes in Letterhead
Sending an email notification to an advertiser when the Newsletter is published
The promotion campaign changed