MC1243552 - High Volume Email for Microsoft 365 upcoming general availability

Updated March 12,May 20, 2026: We’re reminding you that billing for High Volume Email will begin soon. To avoid service disruption, ensure your billing configuration is set up before billing starts. We have updated the content.content below. Thank you for your patience. 

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)Usage will be announced withmetered starting June 1, 2026, based on the GA release, andnumber of expanded delivered recipients. Pricing is $42 per one million recipients (equivalent to $0.000042 per recipient) through Microsoft commerce.

To ensure uninterrupted service, you must configure your billing will beginsettings before billing starts. If billing is not configured by this date, your organization may experience interruption in June 2026 following a free promotional period after GA in March 2026.High Volume Email message delivery until billing is set up.

This message is associated with Microsoft 365 Roadmap ID 382633.

When this will happen

• Public Preview: Available now.
• General Availability (worldwide): Rollout begins in lateAvailable now. 
• Billing for High Volume Email will begin on March 2026 and is expected to complete early AprilJune 1, 2026.

How this affects your organization

Who is affected

• Admins managing Exchange Online mail flow and reporting
• Organizations with large-scale internal email distribution needs

What will happen

• A new High Volume Email page will appear under Mail flow in the Exchange admin center.
• Admins can create and manage Mail User accounts enabled for HVE.
• HVE accounts use a dedicated SMTP endpoint for high-volume sending.
• A new High Volume Email report will appear under Reports > Mail flow to help admins monitor HVE usage per account.
• HVE is opt‑in; it does not modify default sending limits or existing mail flow behavior.

Screenshot 1 - Create new HVE specific accounts: 

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

What you can do to prepare

No actionTo continue using High Volume Email without interruption:

1. (Optional) Review your current usage of High Volume Email. For more information, see View HVE usage report.
2. (Required) Set up billing configuration for High Volume Email. For more information, see Set up Billing for High Volume Email.
3. (Required) Verify that your billing configuration is required to prepare for this change.
   active and correctly associated with your tenant.

You may want to:

• Review and update any internal documentation that describes email‑sending processes.
• Learn more about setup and configuration: Manage high volume emails for Microsoft 365 Public preview | Mail flow best practices | Exchange Online | Microsoft Learn

Compliance considerations

No compliance considerations identified. Review as appropriate for your organization.