Here is the perfect way to start an email — and 18 greetings you should usually avoid

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Figuring out how to start an email — especially when you're writing to someone you don't know very well — can be a real challenge.

Is "Hey" too casual? Is "Dear" overly formal? Is "Morning!" too cheery?

If you're thinking the email greeting isn't all that important and that it's silly to overthink it, you're wrong. How you begin an email sets the tone and may shape the recipient's perception of you. It may also determine whether they keep reading. So, yes, it's very important.

"Many people have strong feelings about what you do to their names and how you address them," Barbara Pachter, a business-etiquette expert, tells Business Insider. "If you offend someone in the salutation, that person may not read any further. It may also affect that person's opinion of you."

We had Pachter and Will Schwalbe, who coauthored "Send: Why People Email So Badly and How to Do It Better" with David Shipley, weigh in on a handful of common email greetings.

Of course, the perfect way to start an email will depend on who you're writing to, but in general, when you're writing a business email to someone you don't know well or at all, they say there's one safe choice — and a bunch you should usually avoid:

WINNER: 'Hi [name], ... '

If you want to make it a little more formal, you can always use the person's last name: "Hi Mrs. Smith, ... "

"The reason I like this one is that it's perfectly friendly and innocuous," says Schwalbe.

It's also Pachter's favorite. She says it's a safe and familiar way to address someone, whether you know them or not.

So when in doubt, go with "Hi."

'Greetings, ... '

This is a good back-up to "Hi, [name] ... " if you don't know the recipient's name. However, you should always do whatever you can to find out that information. 

'Hey!' 

This is fine to use with your friends, but the very informal salutation should stay out of the workplace. It's not professional — especially if you're writing to someone you've never met, says Pachter.

Schwalbe agrees. "I can never get out of my head my grandmother's admonition, 'Hey is for horses.'"

Also avoid "Hey there." It tells the person, "I don't know your name, but if I try to sound cool and casual, maybe you won't notice."