> ## Documentation Index
> Fetch the complete documentation index at: https://docs.open.cx/llms.txt
> Use this file to discover all available pages before exploring further.

# Unsubscribe Contacts

> Your contacts must be able to unsubscribe/opt out of receiving marketing emails.

Your contacts must be able to unsubscribe/opt out of receiving marketing emails.

You can set the `email_is_transactional` field when sending an email to specify its type. If a contact has unsubscribed, and the `email_is_transactional` attribute is set to `false`, the contact will *not* receive the email.

Open enables opting out contacts in two ways:

* An API for generating links that your contacts can click to unsubscribe
* An API for unsubscribing contacts from within your apps

## Unsubscribe Link

You can call [this endpoint](./unsubscribe_url_api) to generate a link that you can put in the body of any email, or anywhere in your application. You can generate this link using the contact's email, or their contact ID.

## Unsubscribe via API call from your apps

In case you want your contacts to unsubscribe in a way other than clicking a link and being redirected to Open, you can directly call [this endpoint](./unsubscribe_directly_api) to mark a contact as unsubscribed from all email.