Some say there is a Gmail feature to schedule emails for later sending, named "Write Now, Send Later".
How do I activate the feature?
You don't have to do anything to activate it. The rollout started yesterday, but it may take 15 days or more for it to be widely available.
From this Google blog post:
Rapid Release domains: Extended rollout (potentially longer than 15 days for feature visibility) starting on April 1, 2019
Scheduled Release domains: Extended rollout (potentially longer than 15 days for feature visibility) starting on April 15, 2019
On/off by default?
- This feature will be ON by default.
The blog post specifically discusses G Suite domains, but the rollout to basic Gmail accounts is likely similar.
Fear not if you haven’t yet got the option, it appears that GSuite users will get the feature first, with the rest of us getting the option very soon.
Meanwhile (or as an alternative) you can use this Gmail add-on which is able to schedule emails: Boomerang for Gmail