No, you do not need to put a date on your cover letter. In the past, most cover letters were sent by mail, so job seekers included the date to make it clear when they sent it. Today, cover letters are primarily submitted online where the date is automatically recorded by either a third-party job portal, email timestamp, or a company’s applicant tracking system.
If you still want to put the date on your cover letter, make sure you format it properly. The correct way to format the date on your cover letter is [Month] [Day], [Year]. For instance, July 29, 2021.