After I add a Customu domain to my Microsoft 365 Business basic. how many custom Domain Emails Adresses can I set up for that 1 user I have

Dear @Godswill Dave,

Thank you for posting your question in the Microsoft Q&A forum.

Based on your description, you are asking how many custom email addresses can be assigned to a single Microsoft 365 Business Basic user after adding a custom domain.

If you have a Microsoft 365 Business Basic subscription and have added a custom domain, a single licensed user mailbox can have up to 400 email aliases (custom email addresses) associated with it. No additional license is required for these aliases.

For example, if your domain is contoso.com, one user could receive email sent to:

• ******@contoso.com (primary address)
• ******@contoso.com
• ******@contoso.com
• ******@contoso.com

All messages sent to these aliases are delivered to the same mailbox

Please note that aliases do not create separate inboxes. If you need separate mailboxes for different purposes, such as Sales or Support, you may want to consider additional mailboxes or a shared mailbox instead.

For more information

Add another email alias for a Microsoft 365 business subscription user

I hope information above meet your expectations, please feel free to reach out if you have any other questions.

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