Microsoft is doubling the size of the mailboxes included with Business Basic, Business Standard, and Business Premium licenses, increasing them from 50 to 100 GB. This update comes a few weeks after the price increase for Microsoft 365 licenses that took effect on July 1, 2026.
At Infologo, in Geneva and Lausanne, we are monitoring this update on our French-speaking Swiss clients’ servers, and as is often the case with Microsoft, it is being rolled out in batches: not all companies have made the switch yet.
In practical terms, users have twice as much email storage space without having to purchase an additional Exchange license. For many companies, this permanently postpones issues related to mailbox capacity and the need for regular archiving.
The new quota applies to the three Business licenses
The Business Basic, Standard, and Premium plans are all being upgraded to 100 GB.
Unlicensed shared storage plans, on the other hand, remain at 50 GB, with no change.
For a company that is approaching this limit on a shared account, adding a license is still necessary, just as it was before this update.
A change that follows the rate increase on July 1
Microsoft is not presenting this change as an official offset for the price increase. The result for the customer remains the same: double the email storage space, with no change to the license or the bill.
What’s Different When Choosing Between Business Basic and Exchange Plan 2
The cost structure for certain licenses changes with this new quota. Exchange Online Plan 1 remains at 50 GB, Business Basic increases to 100 GB, and Exchange Online Plan 2 offers 100 GB plus an additional 1.5 TB of online archiving.
A company that signed up for Plan 2 solely to get more storage may want to reassess that need: Business Basic offers the same storage quota, without the compliance features that are of no use to anyone if they aren’t used.
The Case of the 150 GB Drives: Unexpected and Undocumented Behavior
In several Microsoft 365 environments managed by our teams, some mailboxes that combine a Business license with an Exchange Online Plan 2 are temporarily showing a quota of 150 GB, instead of the advertised 100 GB.
This behavior stems from the way Microsoft allocates the additional 50 GB through a new internal service, and it is not coveredin any official documentation. It should not be considered a guaranteed long-term benefit, and we do not recommend basing a licensing strategy on this 150 GB quota.
What we recommend at Infologo
The key takeaway is the widespread transition to 100 GB Business licenses, not the specific case of the 150 GB licenses. This change enhances the value of Microsoft 365 offerings in response to a recurring challenge: the continuous growth in email volumes.
Before optimizing licenses or deleting an Exchange Online Plan 2, it is still necessary to verify the actual size of the affected mailboxes to avoid any risk of the process being blocked due to a quota reduction.
Would you like to know which accounts have already been upgraded to 100 GB, or identify which licenses could be optimized? Our teams in Geneva and Lausanne offer a no-obligation Microsoft 365 audit.
Article co-authored with Luca Orlanni, an Infologo technician.
