customized domain

To change the default domain of Microsoft 365 to your business domain, follow these steps:

1. Sign in to the Microsoft 365 admin center.
2. Go to Settings > Domains.
3. On the Domains page, select the domain that you want to set as the default.
4. Choose Set as default.

Make sure that your business domain is already added and verified in your Microsoft 365 account before setting it as the default.

After setting your business domain as the default, all new email addresses created will use this domain by default.

References:

• Change your Microsoft 365 email address to use your custom domain
• Add a domain to Microsoft 365

Dear @Micro to Nano Solutions,

Thank you for reaching out to Microsoft Q&A forum.

I understand that you would like to change the default domain name of your Microsoft 365 (M365) tenant to your business’s custom domain (for example, changing from yourcompany.onmicrosoft.com to yourbusinessname.com). This is a standard administrative task that involves verifying and setting up the domain in the Microsoft 365 Admin Center, followed by configuring the DNS records at your domain registrar.

Please note that you must be a Global Administrator to perform these steps.

Kindly review the answer provided by Q&A Assist above to see if it helps. If not, we can work together to resolve this. Thank you for your patience and understanding. If you have any questions or need further assistance, please feel free to share them in the comments so I can continue to support you. I look forward to your reply.

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