Outlook on the web offers the ability to compose an email message, and schedule it to send at a later time. Although similar functionality exists on Outlook for Windows, it is dependent upon you having your computer on with Outlook open and an internet connection. Outlook on the web offers a more reliable way to schedule a message to send at a later time. You do not need to be logged into Outlook on the web at the scheduled send time for the message to send.
Instructions
Open Outlook on the web.
Create and compose your email message. Then select the dropdown menu next to the Send button.
Select Send later:
Select the date and time you would like the email to be delivered and click Send.