---
title: "Exchange Online Tenant Outbound Email Limits (TERRL)"
slug: "exhange-online-tenant-outbound-email-limits"
tags: ["Exchange Online", "External Recipient Limit", "TERRL"]
updated: 2025-10-02T17:56:39Z
published: 2025-10-02T17:56:39Z
canonical: "help.opensense.com/exhange-online-tenant-outbound-email-limits"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://help.opensense.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Exchange Online Tenant Outbound Email Limits (TERRL)

Microsoft is rolling out a new policy in Exchange Online called the **Tenant External Recipient Rate Limit (TERRL)**. This is a tenant-wide restriction that limits how many unique external email addresses a Microsoft 365 tenant can send to within a 24-hour period. The intent is to prevent abuse of the service and ensure consistent performance across all Microsoft customers.

This article outlines the TERRL policy, how it is calculated, when it is enforced, how to monitor it, and what happens if your tenant exceeds its limit.

## What is TERRL?

The **Tenant External Recipient Rate Limit (TERRL)** is a cap on the total number of unique external recipients that can be emailed across your entire tenant within a 24-hour sliding window.

<editor360-custom-block data-preprocessing="false" data-sanitizationtags=""><h4>Key points</h4><ul><li>External recipients are any email addresses not associated with your tenant’s accepted domains.</li><li>The limit is tenant-wide, meaning it includes all messages sent from all users.</li><li>This policy is separate from existing per-mailbox limits and is applied independently.</li></ul></editor360-custom-block>

## How is the Limit Calculated?

The daily external recipient limit for a tenant is calculated using the following formula:

```plaintext
500 * (number of non-trial email licenses ^ 0.7) + 9500
```

#### Sample Limits by License Count

| Number of Licenses | Daily External Recipient Limit |
| --- | --- |
| 1 | 10,000 |
| 2 | 10,312 |
| 10 | 12,006 |
| 25 | 14,259 |
| 100 | 22,059 |
| 1,000 | 72,446 |
| 10,000 | 324,979 |
| 100,000 | 1,590,639 |

<editor360-custom-block data-preprocessing="false" data-sanitizationtags=""><strong>Note:</strong> Trial tenants have a fixed daily limit of <strong>5,000 external recipients</strong>, regardless of license count.
</editor360-custom-block>

## Enforcement Timeline

#### Worldwide (WW) Tenants

| Date | Applies To Tenants With… |
| --- | --- |
| April 3, 2025 | 25 or fewer email licenses |
| April 18, 2025 | 200 or fewer email licenses |
| April 28, 2025 | 500 or fewer email licenses |

<editor360-custom-block data-preprocessing="false" data-sanitizationtags=""><strong>Important:</strong> The final enforcement phase for all remaining WW tenants is currently <strong>paused</strong> according to Microsoft’s official announcement.
</editor360-custom-block>

#### Government Community Cloud (GCC)

| Date | Rollout Phase |
| --- | --- |
| June 30, 2025 | Reporting available in EAC |
| July 30, 2025 | Enforcement begins |

Additional government environments (GCCH, DoD, Gallatin) will follow in the second half of 2025.

## Monitoring Your Usage

#### 1. Exchange Admin Center (EAC)

Navigate to: **Reports > Mail flow > Tenant Outbound External Recipients**

- Total external recipients in the past 24 hours
- Your tenant’s current quota
- Quota usage percentage
- Number of recipients blocked if the limit was exceeded
- Whether enforcement is enabled or disabled

#### 2. PowerShell

```powershell
Get-LimitsEnforcementStatus
```

## What Happens When You Exceed the Limit?

- Messages to external recipients will be blocked.
- Senders will receive a Non-Delivery Report (NDR).

#### NDR Codes

- **Trial tenants:** 550 5.7.232 – Trial tenant exceeded its daily limit
- **Non-trial tenants:** 550 5.7.233 – Tenant exceeded its daily limit

Email sending resumes automatically once usage drops below the limit.

## What Doesn’t Count Toward TERRL?

- Journaling messages created by Exchange Online rules
- Automatic replies (e.g., Out of Office)
- Delivery Status Notifications (e.g., NDRs, receipts)
- Azure Communication Services messages
- System-generated notifications from Microsoft apps (Teams, SharePoint, Yammer)
- Exchange Online High-Volume Email solution messages

## Recommendations for High-Volume Sending

If your organization sends bulk or transactional messages (marketing, alerts, notifications):

- Avoid relying solely on Exchange Online mailboxes for this volume.
- Use [Azure Communication Services](https://learn.microsoft.com/en-us/azure/communication-services/) or other high-volume infrastructure.

## Final Thoughts

TERRL is a strategic policy shift by Microsoft designed to reduce outbound abuse and promote consistent service quality. While it may require new planning and tooling for large-volume senders, it also provides transparent reporting and reliable enforcement.

### Additional Resources:

- Microsoft - [Introducing Exchange Online Tenant Outbound Email Limits](https://techcommunity.microsoft.com/blog/exchange/introducing-exchange-online-tenant-outbound-email-limits/4372797)

### Opensense Support

For further assistance, contact Opensense Support:

- Email: [help@opensense.com](mailto:help@opensense.com)
- Knowledge Base: [help.opensense.com](https://help.opensense.com)