How to add a default owner of all my future Sharepoint's site ?

Hi, unfortunately, the SharePoint admin center does not currently have a built-in feature to automatically set a default owner for all newly created sites. However, you can manually add an admin account to each new site, whether created by Teams or for new modern sites.

Go to the Active sites page of the new SharePoint admin center, and sign in with an account that has admin permissions for your organization.

On the left column, select a site.

Select Permissions. For a group-connected team site, you can add and remove group owners and additional site admins.

Add the admin account as an owner.

For a more automated approach, you could consider using PowerShell to add a Site Collection Admin to all SharePoint Online Sites. This would involve writing a script that retrieves all sites and adds the admin account as a Site Collection Admin.

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Bonjour @Alex Burlachenko et @Ling Zhou_MSFT , First, thanks for your answers.

But currently, when I create a sharepoint site, there is automatically a default site administrator.

I would like to replace this administrator by default.

There are no settings in the microsoft 365 console or in powershell to fill in the default property?

Thanks !

Have a nice day,

JeremieG