An analysis of 350,000 messages found the best way to end an email if you want a response

I've always thought of obsessing over your email openings and closings as a bit like obsessing over your outfit — not worth it.

As long as you don't do something outrageous — say, sign an email to your CEO with "xoxo" or show up to a job interview wearing a clown costume — you'll be fine with whatever you choose.

I was wrong. 

According to a new analysis from Boomerang, an email productivity app, different email sign-offs yield different response rates. And woe to the unappreciative emailers among us: The analysis found that the best way to end an email is with gratitude.

Specifically, results showed that the most effective email sign-off is "thanks in advance."

For the study, Boomerang looked at closings in over 350,000 email threads from mailing list archives in which, they wrote in a blog post, many emails involved "people asking for help or advice, hoping for a reply."

Then they picked out the eight email sign-offs that appeared over 1,000 times each and figured out the response rate linked to each sign-off. Here's what they found: 

• "Thanks in advance" had a response rate of 65.7%
• "Thanks" had a response rate of 63%
• "Thank you" had a response rate of 57.9%
• "Cheers" had a response rate of 54.4%
• "Kind regards" had a response rate of 53.9%
• "Regards" had a response rate of 53.5%
• "Best regards" had a response rate of 52.9%
• "Best" had a response rate of 51.2%

The average response rate for all the emails in their sample was 47.5%.

Explore BI Games

Take a smarter break in your day - and see how far you get.

Play now

Want more Business Insider in your news feed?

Add BI in Google so our reporting is easier to find when you’re searching for what matters.

Add to Preferred Sources

The Boomerang blog post also cites 2010 research from Adam Grant and Francesca Gino, which found that participants who received an email from a student asking for feedback on a cover letter were twice as likely to help when the email included the phrase, "Thanks so much! I am really grateful." 

Interestingly, three separate etiquette experts previously told Business Insider that "best" is the most appropriate way to end an email. And one such expert said that "thanks" is "obnoxious if it's a command disguised as premature gratitude."

The Boomerang analysis didn't measure how recipients felt about the sender — just whether they responded. It also didn't measure the power dynamics at play. Maybe your boss signs their emails "best," and they always get an answer.

Bottom line: If you want a response to your email, it can't hurt to end it with an expression of gratitude. Thanks for reading!