MC1243552 - High Volume Email for Microsoft 365 upcoming general availability

Updated 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 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.

UsageHVE is available at no additional cost during Public Preview. Pricing for General Availability (GA) will be metered starting June 1,announced with the GA release, and billing will begin in May 2026, based on the number 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 settings before billing starts. If billing is not configured by this date, your organization may experience interruption following a free promotional period after GA in High Volume Email message delivery until billing is set up.March 2026.

This message is associated with Microsoft 365 Roadmap ID 382633.

When this will happen

• Public Preview: Available now.
• General Availability (worldwide): Available now. 
• Billing for High Volume Email will begin onRollout begins in late June 1,March 2026 and is expected to complete early April 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

To 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 configurationNo action is required to prepare for High Volume Email. For more information, see Set up Billing for High Volume Email.
3. (Required) Verify that your billing configuration is 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.