The correct spelling of 'e-mail' or 'email' depends on the style guide being used. In the traditional Oxford dictionary, the word is spelled as e-mail. The AP Stylebook and some other respected publications prefer email. Wired magazine favors email, and general sensibly favors that as well. However, when proper names are involved, the Chicago Manual suggests using a hyphen: E-Mail. Similarly, with prefixed terms like e-mailing or e-mails, the Chicago Manual prefers a hyphen, while other publications favor omitting it. Ultimately though, depending on which style guide you follow will dictate how you spell emails - so make sure to check your chosen manual or publication's preference!

But what I figure is that a lawyer wants to know what the Blue Book says. My review of the 21st edition does not show anything on point. It is notable that when the Blue Book does discuss the topic, there is always a hyphen in the word: E-mail. So, I suggest using the hyphen.

Whatever you do, be consistent about it! 🤗