Send & Receive Issues

How to Fix External Recipient Sending Limits for Microsoft 365 Email

Elise Williams Sep 29, 2026 871 views

Question details

The user is unable to send emails, including newsletters and test messages, due to exceeding the daily external recipient sending limit.

How to Fix External Recipient Sending Limits for Microsoft 365 Email

Product: Microsoft 365 (Exchange Online)
Device & OS: not provided
Scenario: Sending bulk emails or newsletters to external contacts from an onmicrosoft.com or Outlook.com domain.
Observed behavior: Microsoft 365 blocks all outbound emails, indicating the tenant's external-recipient sending limit has been exceeded, making the account unusable for sending any messages.

Before you start

Ensure you have Microsoft 365 global administrator or Exchange administrator privileges to access the admin center, review message traces, and unblock restricted entities.

Solution 1Recommended

Investigate and Unblock the Account via Microsoft 365 Defender

Use the Microsoft 365 security portal to check if the user account has been restricted due to sending limits and remove the block.

When an account exceeds the tenant's sending limits, Microsoft automatically places it on the Restricted Entities list to protect the domain's reputation. You must manually unblock the account to restore email functionality.

Access the Defender Portal

Navigate to Restricted Entities

In the left navigation pane, go to Email & collaboration, then click on Review, and select Restricted entities.

Unblock the Account

Find and select the blocked user account from the list, click the Unblock button, and follow the on-screen prompts to confirm.

Propagation Time: It may take up to 1 hour for the unblocking process to fully take effect across Microsoft 365 servers.

Solution 2

Review Message Trace for Unusual Activity

Verify if hidden forwarding rules or a compromised account secretly consumed your daily sending limits.

Solution 3

Contact Microsoft Support for Limit Adjustments

Request support if the limits were triggered incorrectly on a trial or newly created onmicrosoft.com tenant.

Free Microsoft Office alternative

Try WPS Office for Your Document and Mail Merge Needs

While troubleshooting your email limits with Microsoft 365, consider WPS Office as a lightweight, free alternative to Microsoft Office. It offers seamless compatibility with Word, Excel, and PowerPoint formats, making it easy to prepare newsletters, mailing lists, and documents offline without subscription hurdles.

1. Download and Install: Visit the official WPS website to download the free installation package for your operating system.
2. Open Your Documents: Launch WPS Office and easily open your existing Microsoft Word or Excel files to continue preparing your newsletters.
3. Manage Mailing Lists: Use WPS Spreadsheet to organize your external recipients securely offline.

100% compatible with Microsoft Office formats (DOCX, XLSX, PPTX)Create and edit newsletter content easily with WPS WriterManage recipient lists and external contacts efficiently in WPS SpreadsheetFree, lightweight, and features a familiar user interface for smooth migration

microsoft office alternative - wps office

Frequently Asked Questions

What is the external recipient sending limit in Microsoft 365?

By default, Microsoft 365 restricts the number of recipients a user can send emails to within a 24-hour period (often up to 10,000 recipients for paid subscriptions, but heavily reduced for external recipients on new or trial tenants) to prevent spam.

Why was my account blocked when I only sent 195 emails?

If you are using a trial tenant, an onmicrosoft.com domain, or a newly created account, Microsoft imposes much stricter sending limits. Additionally, a compromised account sending unauthorized spam in the background could have exhausted your limit without your knowledge.

How long does the restricted sender block last in Microsoft 365?

Once the sending limit is reached, the user cannot send emails for 24 hours. However, if the account is placed on the Restricted Entities list, an administrator must manually unblock it; otherwise, the block will persist.

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