Send Later is a feature that allows you to schedule emails to be sent at a later date and time. It is available on all the Pro, Premium, and Enterprise plans on our Gmail product.
To set up a scheduled email, open up a compose window in Gmail and write your desired message as you normally would. Instead of sending, click the green ‘Later’ button at the bottom of the screen and choose the date that you’d like for your message to be sent.
If you'd like to cancel or edit the scheduled email, simply locate the message in the your Draft folder, click the arrow next to "Send on...", then select a new date, time, or "unschedule" to remove it entirely.