DKIM and the "via" label in Gmail

Gmail made a recent change to help people identify spoofed email and verify the identity of senders in your Inbox. It’s a great addition, especially knowing how easy it is to send email pretending to be someone else. As part of this change, Gmail added a subtle but important label in the ‘From’ address field for emails called “via.” This is added for any emails that are sent from third-party senders like Postmark or Newsberry. Here is what it looks like:

What is pm.mtasv.net? #

This is the return-path domain that Postmark uses to send emails. We use it to identify ourselves, build a reputation and process bounce messages. If emails did not come from a domain we owned we would not have the control we need over delivery, reputation and bounce statistics that help us run the service.

Wait! But I don’t want people to see that! #

Of course not. And neither does Gmail, if your sending is optimally configured. To make sure this bit of information does not show up in emails you send to Gmail, all you have to do is make sure you are signing your messages with DKIM. We make this process very easy. Once you start signing with DKIM, that “via sender” does not display anymore. If you visit the “Signatures” tab in your Postmark account, you’ll see tools to configure and even verify the optimal DKIM configuration. It does require access to your DNS configuration, so you may need some assistance. Email support and we can guide you through it.

What if I send on behalf of other customers? #

If you can’t set up DKIM by adding records to your DNS, then the “via pm.mtasv.net” will still display. This is how Gmail intends it, as the message is not coming from your own domain (it’s also why we strongly encourage other methods when you want to make it look like emails are coming from your customers directly). To make the process less confusing for recipients, we have a simple HTML page that explains “pm.mtasv.net”, showing that you, our customers, are serious about email delivery.