increase the storage capacity in primary mailbox without done on our end

Question

noticed that the primary mailbox storage capacity for all Exchange Online users in our Microsoft 365 tenant has changed from 50 GB to 100 GB. is there officially revised the mailbox storage limit for

Answer 1

Dear @Quadra CSS Duty Manager,

The published Exchange Online mailbox storage limit still depends on the user’s assigned license. Microsoft’s Exchange Online limits page continues to show 50 GB for Microsoft 365 Business Basic, Business Standard, and Business Premium user mailboxes, while 100 GB is listed for plans such as Exchange Online Plan 2, Microsoft 365/Office 365 E3, and E5.

It is noted that service limits may differ depending on the tenant and that when limits are changed in Microsoft datacenters, it may take time for changes to apply across existing customers. Therefore, if your tenant’s primary mailbox quota has increased to 100 GB without any action from your side, it may be due to a Microsoft-side service or licensing quota update.

Here are some references:

• Exchange Online limits - Service Descriptions | Microsoft Learn
• Increase or customize Exchange Online mailbox size - Exchange | Microsoft Learn

If you need more detailed information, I recommend you raising a support ticket. A technical support engineer can perform a remote session to investigate the situation verify the backend configurations, and run any necessary synchronization tools to resolve the problem. If the issue requires further attention, they can refer it to a specialized team for deeper analysis. Get support - Microsoft 365 admin | Microsoft Learn

I hope the information shared helps point you in the right direction.

As a moderator, I do not have the tools to investigate your specific account directly, as this is a support forum between users. Moderators and collaborators, including external Microsoft employees, may not directly intervene in the functionality of Microsoft products or access internal systems. Our role is limited to providing technical guidance on reported problems, requests, or ideas. However, I will do my best to guide you as clearly as possible.

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