Different regional settings for users in the same Excel workbook

No. Excel for the web does not automatically apply each user’s Microsoft 365/Entra ID regional settings for the same workbook.

For organization accounts, the default regional format in Excel for the web comes from the SharePoint site regional settings where the workbook is hosted. A user can override that only for their own Excel for the web session by changing File > Options > Regional Settings. That preference applies only to that user’s view of the workbook and does not affect how other people view it.

Important limits:

• The per-user override is manual.
• It requires third-party cookies to be enabled in the browser.
• It is available only for files stored on Microsoft hosts.
• There is no built-in Microsoft 365 admin setting to enforce this globally across the organization.

So for users in Switzerland and the UK viewing the same workbook, each user can have their own regional format, but Excel for the web will not switch automatically based on their Microsoft 365/Entra ID regional profile. Each user must set it in Excel for the web if the SharePoint site default is not suitable.

References:

• Change regional format settings in Excel for the web
• Can i change the Date-Format in OneDrive for my entire organization? - Microsoft Q&A