What is your opinion on using "Dear All," in business emails when addressing to a group of people? Is this too informal? Or has it been an accepted usage?
The situation is that I know all the recipients but I can't find a simple term that can represent all of them. The recipients include my colleagues and external parties. There are a number of alternatives but I think none of them fits in the situation.
Dear Sirs - sexist
Dear Ladies and Gentlemen - seems too formal and outdated
Dear Colleagues - not all of them are colleagues, some are external parties
Dear (name of committee, etc.) Members - not all of them are members
Do you have any other suggestions?
Have you considered the alternative of simply not having any greeting at all? You could just start with the substance of what you want to communicate, such as:
Please note that the next meeting will be on . . .
Email today does not always follow the same standards as non-email. Email is seen as a no-nonsense, let's be quick and practical kind of medium.
If it is a matter where you want to adhere to a very high standard of formal politeness, some people would argue that you should forget about email and write a traditional letter, via the mail or by courier.
I use "Hello everyone" routinely in addressing e-mail to a large group of people.
Do NOT use "To whom it may concern" because, as ecopsy has pointed out, you know exactly who you are writing to.
I also use "Ladies" when writing to addressees who are all women, and "Gentlemen" when writing to all men, and have done a "Ladies/Gentlemen" in situations when I thought "Hello everybody" might sound too informal.
"Dear All" is OK but as a general rule I wouldn't use it. "Dear Sirs" should not be used as that sounds a little awkward. Normally, I would use Dear (department you are writing to), or Dear Colleagues is acceptable.