Microsoft has now started offering Outlook.com Premium email services without an invite, though there hasn’t been any official announcement.
Why Outlook.com Premium?
The Premium service doesn’t show any kind of ads and it supports custom domain name as well. You can either get the domain from Microsoft or add your own domain to the account. After that you can have 5 personalized email addresses, like email@example.com.
Outlook Premium also helps you easily share calendars, contacts, and documents (via OneDrive) between those five users.
The Premium service costs around $50 per year, but if you subscribe before March 31 you’ll only have to pay $20.