How do you write a formal email?

Question

What is the web equivalent of formal letters? In this day and age, formal correspondence have all become digital, and it would be helpful to know the proper way.

Oh, and please do highlight if there are different styles (the classic American vs British, maybe?) and how they differ.

Answer 1

Formal style in email is appropriate in a variety of situations: job-seeking, academia and business (especially when writing to someone more senior), and when you make a request of someone you don't know personally.

If the other person or organization has set the tone first, you may want to try to match it or be only a little more formal in a response; consider email a note rather than a full letter. For example, if I dash off a message to let a webmaster know about a problem, I may use "Hi," and "Thanks!" But my boss may send me a message without any salutation or signature and I'll nearly always use one in my response:

Jane Doe —
Body of email.
Thanks,
My Name
My Automatically Appended Signature Block (other methods of contact here)

You may find this reference helpful, by Adam Turner, HYU CTL - it's designed for non-native speakers in academia, but I'd recommend the general guidelines to anyone: English Solutions for Graduate Research Writing: Formal Email [PDF], or the short version, a handout focusing on email style [PDF]. The first reference discusses subtleties in salutations:

Correct punctuation is important because it can show the relationship between the speakers. It is meaningful. When I email other English professors for the first time, I often start like this:
Dear Professor Taylor:
After we exchange email and I know a bit more about the person, such as that they are a similar age and status, I might change to
Dear Professor Taylor,
Finally, as we get to know each other or after we have met in person, I might change my greeting to
Dear Robert,

I'm not sure everyone will be sensitive to all levels of punctuation here, but you're unlikely to go wrong with this format.

This reference also gives some great examples of how to couch requests politely in formal email. The guidelines given seem appropriate for an American business audience, certainly. An excerpt:

Don’t demand or ask for a positive result, whether it is for a job or a journal article. Examples ...
[NO]: I am waiting for your answer soon.
[NO]: I expect that I get help from you.
[YES]: Thank you for considering my application. ...
[YES]: I look forward to your reply.
[YES]: If you have any questions or require further information, please do not hesitate to contact me at...

Answer 2

I assume you're referring essentially to e-mails rather than anything web-specific (like filling in forms on web pages).

As in many languages, the notion of "formal" vs "informal" in e-mails has largely gone out of the window. My observations from business correspondence and other "formal" uses of e-mail would be:

• Use of "Dear" as the opening salutation rather than "Hi" or "Hello" (although if appropriate, things like "To whom it may concern", "FAO webmaster of randomdomain.com" etc could also start an e-mail);
• Avoidance of overly informal language in the body of the e-mail;
• Use of a short, neutral closing salutation such as "Regards", "Best regards", "Best", "Best wishes" (people don't tend to use things like "Yours sincerely/faithfully" etc so much in an e-mail as they might in a letter);
• Inclusion of a signature that mentions corporate things such as a confidentiality policy etc as well as contact details.

And that's more or less it as far as English is concerned. The e-mail medium seems to be overall less formal than traditional mail.