Remember, this should be a specific date, timeline, schedule, or urgency. Without a deadline there is no call to action and nothing gets done. Readers need deadlines.
It’s often critical that you explain the deadline so readers can see its importance. Give a reason or consequence for a missed deadline.
About 95% of emails do not have a concrete deadline. Most end with abstract clichés like “prompt attention to this matter,” or “at your earliest convenience,” or “as soon as possible.” These clichés have been used for centuries because they sound courteous and abstract enough to avoid accountability.