Domain transfer refers to the process of changing the registrar for a domain. When you transfer a domain, you change who you send payments to in order to renew and keep your domain name.

To use your domain with Office 365, you don’t transfer it to Office 365. Instead, you go through a process where you "add" your domain, prove that you own the domain, then you make certain updates to your domain records to associate it with your Office 365 services, such as Exchange Online for your email. Your relationship with your current domain registrar doesn’t change. You continue to send your payments to them for domain renewals. For more information, see Add your domain to Office 365 for enterprises or for professionals and small businesses.