7 common mistakes people make when writing email subject lines

'Ideas' or 'Meeting'

Anything too vague is going to be skipped over, Leonov said. Unforunately, that's a common mistake.

Not only does a vague subject prompt the recipient to gloss over your note, it makes it difficult for people to find the email later. Leonov said it's important to make sure your email can be quickly picked up when your colleague is searching for the note in a few days or weeks.

"Making the subject specific and descriptive will make it easier to find later," Leonov said.

'Hey'

This has a similar effect to using a super-vague message as your subject line. Writing "Hello [Name]" or something of the sort is a misguided attempt at being casual, and it likely just comes off as annoying and inconsiderate to the person you're messaging.

"Think about the recipient and imagine that your email is one of ten thousand that the person has to go through," writes tech marketer Hillel Fuld on Inc. "If that were the case, would you still have written 'Hey' as a subject line? Probably not."

'Can I offer you some free help?' or 'Get the BEST thing you need from ME'

Certain words can make your email go right to the spam folder. That includes "amazing," "risk free," and "winner," according to OptinMonster.

"You might think you've stumbled on a clever trick that no one has thought of before, but with 30 years of email and roughly 193 gajillion spams sent, almost every cheezy, tacky, tricky come-on line has been tried, and caught, by the filters of the email inboxes of the world," Marc Cenedella, CEO of Ladders, told Business Insider.

Even if you manage to bypass the spam filter, a clickbait-y subject line will likely cause your colleague or potential contact to roll their eyes and ignore your message.

'(No subject)'

Even a bad subject line is better than no subject line.

"An email with a blank subject line will likely get deleted, lost, or immediately irritate the recipient, who is forced to open the email to figure out what it's about," Business Insider previously reported.

'Let's get coffee or lunch maybe on Tuesday? I'm not sure, we can also do Wednesday or the next week, but I have a doctor's appointment and...'

Keep your email subjects 50 characters or fewer, suggests HubSpot. Email subject lines can cut off if they get too long, particularly if opened on mobile.

'Let's talk about case number 23904890384'

Yes, specificity is important in email subject lines. But, according to HubSpot, you don't need to include the nitty-gritty details.

Instead of going all in on the numbers and specificities of a certain situation, describe in a few words what the situation is.

"'Your order' is better than 'order number 91208310,'" HubSpot writes.

'WE HAVE A NEW VACATION POLICY!!!'

Plenty of folks still rely on all-caps subject lines — and while the thought may be that it's attention-grabbing, the move will likely just alienate whoever you're contacting.

"It can come across as though you are yelling," advises email marketing platform AWeber. "So you should use capitalization and punctuation cautiously."