Starting October 26th, 2023, any marketing emails, including those manually sent or sent through automation that use a personalization token to populate the "From" address field, will require email verification. If an email address is not verified, it will be subject to a variable domain process.

The verification will help reduce security risks when sending emails from unverified email addresses. For example, when sending a marketing email, you must verify the email address added to the "From" address field using personalization tokens.

What does this mean for developers?

No marketing email sends will be stopped with this change. However, any unverified emails will be subject to a variable domain process. For example:

1. If a customer’s envelope sender domain (ESD) is user@registereddomain.com
2. The user attempts to send an email from an unverified email address: user@attempt.com
3. HubSpot will modify the email address to read as user=attempt.com@registereddomain.com

Users will still be able to send the email, but the "From" address will be modified to denote the email is coming from an unverified email address. Therefore, verifying all email addresses that could be added to the "From" address via a personalization token is essential.

Please let us know if you have any feedback or questions by joining the conversation in the Developer Community forum.