Microsoft 365 is introducing High Volume Email (HVE) for large-scale internal communications, available now in Public Preview and generally available March 2026. HVE offers dedicated SMTP endpoints, new admin controls, and reporting, with a transactional pricing model starting May 2026 after a free promotional period.
Introduction
Exchange Online includes email‑sending limits based on three factors: recipient rate limit, recipient limit, and message rate limit. To support customers whose internal communication needs exceed these standard limits, we are introducing High Volume Email (HVE) for Microsoft 365. HVE is designed for large‑scale internal communications and integrates with business applications and devices to support operational and mass‑mailing scenarios. It uses a transactional pricing model based on the number of recipients.
HVE is available at no additional cost during Public Preview. Pricing for General Availability (GA) will be announced with the GA release, and billing will begin in May 2026 following a free promotional period after GA in March 2026.
This message is associated with Microsoft 365 Roadmap ID 382633.
When this will happen
How this affects your organization
Who is affected
What will happen
Screenshot 1 - Create new HVE specific accounts:

Screenshot 2 - Manage HVE accounts, including assigned billing policies:

What you can do to prepare
No action is required to prepare for this change.
You may want to:
Compliance considerations
No compliance considerations identified. Review as appropriate for your organization.