---
title: "Domain Setup"
description: "Setting up MX records for inbound email delivery"
canonical_url: "https://smtp.dev/docs/setup/domain/"
last_updated: "2026-08-16T22:38:03.995Z"
---

## MX Record

After adding your domain to our system, you'll need to point it to our mail servers:

### Required DNS Record

<table>
<thead>
  <tr>
    <th>
      Type
    </th>
    
    <th>
      Name
    </th>
    
    <th>
      Value
    </th>
    
    <th>
      TTL
    </th>
  </tr>
</thead>

<tbody>
  <tr>
    <td>
      MX
    </td>
    
    <td>
      @
    </td>
    
    <td>
      mx.smtp.dev
    </td>
    
    <td>
      3600
    </td>
  </tr>
</tbody>
</table>

### Setup Instructions

<steps level="4">

#### **Log in to your domain/DNS provider's website**

#### **Find the DNS settings or Domain management section**

#### **Create a new MX record with exactly the values shown above**

</steps>

### Please Note

<note>

DNS changes don't propagate instantly - it could take anywhere from a few minutes to 24+ hours depending on your DNS provider. If you've just updated MX records, expect spotty email delivery until propagation completes. Some providers like Cloudflare are pretty quick (usually a few minutes).

</note>

## Using Subdomains

Subdomains work the same way as root domains.

### Subdomain Email Setup

<table>
<thead>
  <tr>
    <th>
      Type
    </th>
    
    <th>
      Name
    </th>
    
    <th>
      Value
    </th>
    
    <th>
      TTL
    </th>
  </tr>
</thead>

<tbody>
  <tr>
    <td>
      MX
    </td>
    
    <td>
      test
    </td>
    
    <td>
      mx.smtp.dev
    </td>
    
    <td>
      3600
    </td>
  </tr>
  
  <tr>
    <td>
      MX
    </td>
    
    <td>
      support
    </td>
    
    <td>
      mx.smtp.dev
    </td>
    
    <td>
      3600
    </td>
  </tr>
</tbody>
</table>

In this example, both `test.example.com` and `support.example.com` would be configured to receive email.

### Why Use Subdomains?

- Keep your root domain on its real email provider while `test.example.com` receives in the sandbox
- Separate concerns per subdomain (notifications, support, billing)
- Test email configurations without touching your main domain's reputation

<note>

Each subdomain must be added separately before configuring its MX records. For example, to use `support.example.com` and `billing.example.com`, you need to add both domains individually in your dashboard.

</note>

### Setting Up a Subdomain

Let's say you want emails to arrive at `help@support.example.com`:

<steps level="4">

#### **Add the subdomain in dashboard**

Go to the [Domains](/domains) section of your dashboard and add `support.example.com` as a new domain

#### **Configure DNS for the subdomain**

Add an MX record for your subdomain:

<table>
<thead>
  <tr>
    <th>
      Type
    </th>
    
    <th>
      Name
    </th>
    
    <th>
      Value
    </th>
    
    <th>
      TTL
    </th>
  </tr>
</thead>

<tbody>
  <tr>
    <td>
      MX
    </td>
    
    <td>
      support
    </td>
    
    <td>
      mx.smtp.dev
    </td>
    
    <td>
      3600
    </td>
  </tr>
</tbody>
</table>

#### **Create a new Account**

Create a new account and select the `support.example.com` as the domain name

#### **Wait for DNS propagation**

Once DNS propagation completes, you can receive emails at any address `@support.example.com`

</steps>

### Troubleshooting

If emails aren't arriving after updating your MX records:

<steps level="4">

#### **Verify your DNS configuration**

Check your MX setup using [Google's DNS Toolbox](https://toolbox.googleapps.com/apps/dig/#MX/) by entering your domain name. This tool will confirm if your MX record is correctly configured and visible across the internet.

#### **Ensure single MX record configuration**

Your domain should have only one MX record pointing to `mx.smtp.dev`. Multiple or competing MX records will interfere with proper mail delivery. Remove any existing MX records from previous email providers before adding ours.

</steps>

If problems persist, please contact our support team for additional assistance.