Knowledge base

Sender identities

Starter plan users can send emails on behalf of clients, without the need to verify their domain, by creating a sender identity. A sender identity can be attached to verified domains, and enables you to verify an email address of your client and then use that Email Address (and the specified name) to send emails from. 

This is a great solution for sending email on behalf of your clients, as you will be able to send emails from their domain without the need to have them update their DNS records

How to create a sender identity

Creating a sender identity is simple, takes just a few minutes and involves verifying the email address you would like to send from. You can create a sender identity in your dashboard (via API coming soon).

Create a sender identity

From the left-hand navigation menu on the dashboard, go to the Sender identities page. Click on New sender to create a new sender identity.

View of the sender identities page

You’ll be prompted to select the domain you want to add the sender identity to and to add the sender email address, sender name, reply-to address, reply-to name, and a personal note.

Screenshot of the screen to set up a new sender identity in MailerSend.

An email will be sent to the from email address you have specified to verify it manually. In order to use the email address, the owner of the email address will have to verify it by clicking on the link received in the email. 

Again, we recommend that you add a personal note to explain the process and purpose of the verification email to its recipient.

Example of an email verification email that will be sent to the owner of the sender identity email address.

Get notified when an email address is verified

You can set up a webhook to be notified when an email address is verified. In this case, the event is sender_identity.verified

To set up a webhook to your domain, see our instructions on adding webhooks.

Limitations

You can only add a sender identity on a verified domain, and the sender identity must be verified to enable email sending. The sender identity’s domain must be a custom domain and cannot originate from a free email provider.

As soon as the new sender identity is verified, you will be able to start sending emails from that email address ✅

Please be aware, if you attempt to use sender identities from domains you do not own, your emails may not be delivered if the sender identity’s domain has a DMARC policy set to p=reject. In these cases, we recommend adjusting the DMARC policy to p=none or p=quarantine. The latter directs emails to the recipient's junk/spam folder, allowing emails to be accepted by Internet Service Providers (ISPs) but with altered deliverability.

It's crucial to note that sender identities can negatively impact email deliverability due to unaligned headers and lack of authentication, potentially leading to emails being marked as spam or failing to reach the intended inbox.

To enhance deliverability and ensure the integrity of your sender identity, consider utilizing MailerCheck. Adding your domain to the DMARC report feature in MailerCheck will help you to establish a more effective DMARC policy, as well as allows you to monitor how your emails are received by ISPs.

How to add a sender identity to an email

Once you’ve successfully added a sender identity, you will be able to add it to an API call to send an email. You'll use a POST request to the email endpoint, entering the sender identity email address instead of your domain’s usual from address.

For example, instead of using this call:

{
   "from":{
      "email":"admin@web-agency.com",
      "name":"Amy from Book Shelf"
   },
   "reply_to":{
      "email":"support@web-agency.com",
      "name":"Book Shelf Support"
   },
   "to":[
      {
         "email":"jane.doe@gmail.com"
      }
   ],
   "subject":"Hello from The Book Shelf!",
   "template_id":"pq3enl6zrm42vwrz"
}

You'll use this call:

{
   "from":{
      "email":"amy@bookshelf.com",
      "name":"Amy from Book Shelf"
   },
   "reply_to":{
      "email":"support@bookshelf.com",
      "name":"Book Shelf Support"
   },
   "to":[
      {
         "email":"john@mailersend.com"
      }
   ],
   "subject":"Hello from The Book Shelf!",
   "template_id":"pq3enl6zrm42vwrz"
}

All messages, activity, recipients and statistics will be shown under the web-agency.com reports. For example, if you GET a list of activities with the verified domain ID as a parameter, emails sent with that sender identity will be shown.