> This page is part of the [Customer.io documentation](https://docs-customerio.netlify.app). For the complete index, see [llms.txt](https://docs-customerio.netlify.app/llms.txt).
> Last updated: November 5, 2025

# Use your Mailgun Account

You can use your Mailgun account to send email through Customer.io with no loss in functionality. To take advantage of Mailgun, you need to do two things:

1.  [Point Mailgun’s webhooks at Customer.io](#webhooks).
2.  [Configure Mailgun as a custom SMTP server in Customer.io](#custom-smtp).

## Point Mailgun’s webhooks at Customer.io[](#webhooks)

1.  Go to the [Mailgun webhooks page](https://app.mailgun.com/app/sending/domains/cio1.a.customer.io/webhooks).
    
2.  Enter the webhook URL that corresponds to your region for the events you want to forward to Customer.io.
    
    *   US: `https://track.customer.io/mailgun/events`
    *   EU: `https://track-eu.customer.io/mailgun/events`
    
    [![Example US webhook config](https://docs.customer.io/images/mailgun_webhooks.png)](#d712d0e823add948cde98fff35b50019-lightbox)
    

 Do not send *Clicks* or *Opens* to Customer.io!

Customer.io already tracks this information. If you send these webhooks, we’ll record each event twice (once natively in Customer.io and again via Mailgun webhook).

If you want to track opens and clicks via Mailgun and not Customer.io, you can change [tracking settings](/journeys/link-tracking/#emails) on an email by email basis.

## Configure Customer.io custom SMTP settings[](#custom-smtp)

Before you begin, you need your Mailgun SMTP credentials. This integration uses port 587. If you need to use a different port, you should use a [custom SMTP integration](/journeys/use-your-smtp-server/).

[Mailgun config settings](//fast.customer.io/s/sender.customeriomail.com_-_Mailgun_2014-12-29_11-20-08_2014-12-29_11-20-33.png)

1.  Go to [**Settings** > **Workspace Settings**](https://fly.customer.io/workspaces/last/settings/).
2.  Click **Email**, click **Custom SMTP Settings**, and then click **Add Custom SMTP Server**.
    
    [![Custom SMTP settings page](https://docs.customer.io/images/smtp_settings_no_servers.png)](#e716d23f8203dc611fab77ba40838a5f-lightbox)
    
3.  Select **Mailgun** and click **Continue to set up**.
4.  If you haven’t set up webhooks yet, copy the URL on the **Set up webhooks** tab and then [set up webhooks](#webhooks) to report message metrics in Customer.io.
5.  Click **Add Credentials** and enter your Mailgun credentials.
    
    [![Adding one custom SMTP server.png](https://docs.customer.io/images/smtp_settings_mailgun_creds.png)](#2dc4a38b5a573822a282a448c7cc21c3-lightbox)
    
6.  Click **Finish set up**. Your account is now set up to send email through Mailgun. If you have any questions or feedback, [contact us](https://customer.io/contact/) and we’ll be happy to help!

 Configure multiple servers to use both transactional and broadcast streams

If you have a Premium Customer.io plan, you can configure [multiple custom SMTP servers](/journeys/multiple-smtp-servers/) and assign one to each of your Mailgun server types.