Microsoft 365 receives High Volume Email (HVE), upto 100K recipients daily

Microsoft 365 announced the public preview of High Volume Email (HVE), a service for organizations that send large numbers of internal emails. HVE bypasses the limitations of regular Exchange Online mailboxes, allowing for mass email communication from line-of-business applications and devices.

HVE has some decent features designed for your email communication capabilities; it enables the sending of emails to a substantially larger audience than what is possible with a standard mailbox, removing any limitations on the volume of emails you can send. Additionally, it imposes no restrictions on the number of internal recipients.

HVE offers flexible controls for administrators. They can set sending limits and monitor usage on a per-account basis, features that will be available upon general availability. 

Looking ahead, HVE plans to introduce a consumption-based billing model. This future development means that you will only pay for the emails you actually send.

• The service is free to use during the preview but is limited to sending to 100,000 recipients daily. 
• Only 20 HVE accounts can be created per tenant during the preview. 
• Sending is capped at 2,000 external recipients per day. 
• Currently uses basic SMTP authentication, with OAuth support planned for general availability.

To get started with the public preview of HVE, you need to create MailUsers within Exchange Online. As an admin, you can manage HVE accounts, access usage reports, and configure email sending via the Exchange admin center. You should use the dedicated SMTP endpoint (smtp-hve.office365.com) to send emails through HVE.

Microsoft’s Security Defaults feature disables HVE. Ensure it’s disabled so that HVE can function.

More here.