OUTLOOK EMAIL SIZE UPGRADE

Question

Dear Microsoft Team,

 

Good Day!

I would like to inquire regarding our email folder size, if how much is the maximum size.

Because right now our group email is always running out of space. I just want to ask if we can back up in google, cloud, etc.

Or if we want to upgrade the size how much will be the maximum size and how much.

 

Your prompt reply is highly appreciated.

But if you have contact number kindly share so we discuss it with you.

 

Thank you.

 

Answer 1

Hi @Extol International

Thank you for sharing your concern regarding the storage limit of your group email mailbox.

First, I’d like to clarify that this is a user‑to‑user support forum. Moderators participating here do not have access to backend systems, nor can we directly intervene in Microsoft product functionality. Our role is limited to providing technical guidance and sharing best‑practice recommendations based on reported issues, requests, and scenarios.      

I understand that you are experiencing issues with the group mailbox frequently running out of space. 

For Microsoft 365 Group Mailboxes, the maximum storage capacity is 50 GB. This is a fixed Microsoft limitation and cannot be increased, even by assigning additional licenses such as Microsoft 365 E3 or E5. 

In this scenario, I would recommend migrating the group email to a Shared Mailbox, which is designed specifically for shared access by multiple users. This can help address your storage challenges, such as: 

Increased storage: A Shared Mailbox includes 50 GB by default. By assigning one license (Exchange Online Plan 2 or Microsoft 365 E3/E5), the mailbox capacity can be increased to 100 GB. 

Archive capability (if licensed): When properly licensed, a Shared Mailbox can also support an Online Archive, allowing older emails to be archived automatically and helping to prevent the primary mailbox from reaching its size limit. 

For long‑term retention and to prevent storage issues going forward, I additionally recommend one of the following approaches: 

Move or archive older emails to a licensed User Mailbox with Microsoft 365 E3/E5, which supports Online Archive with auto‑expanding storage 

Or you could export older emails to PST files and store them securely in OneDrive. 

These options provide reliable long‑term storage while keeping the shared mailbox optimized for active use. 

 You can refer more via:  

Microsoft 365 Group mailbox size management - Microsoft 365 admin | Microsoft Learn 

Learn about auto-expanding archiving | Microsoft Learn 

Compare Microsoft Exchange Online Plans Microsoft 365 

I hope this helps. 

Please feel free to correct me if I misunderstood your request. If you have any additional concerns, feel free to comment below. I would be more than happy to assist. 

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Answer 2

For business (work or school) Outlook accounts hosted in Exchange Online, mailbox storage can be up to 100 GB per mailbox. Administrators can also configure smaller limits per user or globally.

To check and clean up mailbox storage in Outlook on the web or the new Outlook for Windows:

1. Open Outlook on the web or the new Outlook.
2. Select Settings > Account (or Accounts) > Storage.
3. Review the breakdown of how much space each folder is using.
4. Use the Clean up Mailbox options to permanently delete all items, or items older than 3, 6, or 12 months, in selected folders.

If the mailbox is frequently running out of space, an Exchange Online administrator in the organization can:

• Verify the current mailbox size limit for the group mailbox.
• Increase the mailbox size limit (up to 100 GB) according to the organization’s Exchange Online configuration and licensing.

Regarding backup to Google or other cloud services, that is outside the scope of the provided information. The documented options focus on cleaning up and managing mailbox storage within Outlook and Exchange Online.

For pricing and licensing details (for example, which plans include 100 GB mailboxes), refer to the organization’s Microsoft 365 subscription information or the Microsoft 365 admin/billing portal.

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References:

• Mailbox storage limits in Outlook