https://support.office.com/en-us/article/Set-up-email-in-Outlook-for-iOS-mobile-app-b2de2161-cc1d-49ef-9ef9-81acd1c8e234?ui=en-US&rs=en-US&ad=US 


For server settings, set the following if available:


Incoming Server Settings


Domain\Username 


Make sure your full email address appears. For example, [email protected].


Password 


Use the password that you use to access your email.


Server 



Enter eas.outlook.com for any email account ending with @outlook.com, @hotmail.com, @msn.com, or @live.com, including any other accounts hosted on Outlook.com.


Use outlook.office365.com for any work or school accounts hosted on Office 365 for business.


NOTE: If you're setting up an Exchange-based account and you don't know the name of your Exchange Server, contact your administrator.


Port 


Use 443 or 993.


Security type 


Select SSL/TLS or make sure the Use secure connection (SSL) checkbox is checked, then tap Next.


Outgoing SMTP Server Settings


SMTP Server 



Use smtp-mail.outlook.com if you're using an Outlook.com account.


Use smtp.office365.com if you have an Office 365 for business account.


For Exchange email accounts, contact your email provider or system administrator.


Security Type 


Choose TLS.


Port Number 


Enter 587. Tap Next.