User guide

API reference


Inbound domain forwarding

If you have access to your DNS records, Postmark includes a simple way for you to configure your MX records to point to our mail servers. If you do not have access to your DNS records, we support email being forwarded by 3rd party mail services.

1. Set an MX Record

Choose a domain that you would like to listen on for incoming email to be processed by Postmark. We recommend a separate subdomain, like In your DNS configuration, create an MX record that points to and give it a value of 10.

You may also use a "wildcard" inbound domain such as * which will cause all messages addressed to any subomdain of to be routed to your inbound endpoint. For example, if you register * with Postmark and your DNS host, you may then use an inbound address such as and it will be routed to your inbound endpoint.

Example DNS configuration

2. Set the domain

Inbound domains are unique across Postmark and are server-specific. You can configure the Inbound Domain on the server settings page.

Set the Inbound Domain using the UI

Alternatively, you can use the Server API to set the Inbound Domain on your server.

3. Enable SMTP

Enable SMTP on the server’s outbound settings page.

Enable SMTP

4. Send emails

You should now be able to send emails to any address for

Example request with curl

curl "" \
  -X PUT \
  -H "Accept: application/json" \
  -H "Content-Type: application/json" \
  -H "X-Postmark-Account-Token: account token" \
  -d "{InboundDomain: ''}"

Example JSON response

  "Name": "Production Testing",
  "Color": "blue",
  "SmtpApiActivated": false,
  "RawEmailEnabled": false,
  "InboundHookUrl": "",
  "BounceHookUrl": "",
  "OpenHookUrl": "",
  "PostFirstOpenOnly": false,
  "InboundDomain": ""