This company has an ingenious way to free employees from email on vacation

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American workers had 206 million unused vacation days last year — that's $66.4 billion worth of benefits left on the table.

Many professionals may think the less time they take away from the office the more likely they are to impress their boss. A study from Project: Time Off found the opposite: It said employees who use their vacation days are actually more likely to get a promotion or raise, versus employees who end the year with unused time off.

German automaker Daimler has implemented a "Mail on Holiday" email policy that ensures its employees are taking full advantage of their time off, without fearing an overflowing inbox when they return. Through this policy, employees have the option to set their emails to autodelete while away from the office.

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If you email a Daimler employee who is on vacation, spokesperson Sabrina Schrimpf tells CNBC Make It, you will get a three-option response letting you know that your email will be deleted, that you have the option to email a colleague if it's an emergency or you can email again once the employee has returned to work.

In a TED Talk earlier this year, psychologist Adam Alter described Daimler's messages as saying, "This person's on vacation, so we've deleted your email. This person will never see the email you just sent. You can email back in a couple of weeks, or you can email someone else."

According to Schrimpf, the policy was implemented after employers and managers were asked about their work-life balance and ways to improve it. In 2013, the company started "Mail on Holiday" pilot projects and after receiving positive feedback from its employees, the policy was officially launched in 2014.

"As far as I know, it's a big relief for my colleagues," said Schrimpf. "It's more relaxing not having emails after you return from vacation."

In his TED Talk, Alter praised Daimler for the email system that allows employees to completely step away from work and explained how spending too much time staring at screens can make us unhappy.

"One of the reasons we spend so much time on these apps that make us unhappy is they rob us of stopping cues," said Alter. "Stopping cues were everywhere in the 20th century. They were baked into everything we did."

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He explains a stopping cue as something that signals a need to move on. For example, when someone is done reading a newspaper, a magazine or done watching a television show they stop and move on to the next thing.

"But the way we consume media today is such that there are no stopping cues," he said. "The news feed just rolls on, and everything's bottomless: Twitter, Facebook, Instagram, email, text messaging, the news."

While not everyone is fortunate enough to work for a company that has adopted policies like Daimler's, Alter says there are some practices professionals can enforce in their personal lives to ensure they aren't tied to their screen beyond the office.

For him, that stop cue is the start of dinner.

"At first, it hurts. I had massive FOMO," he said. "But what happens is, you get used to it. You overcome the withdrawal the same way you would from a drug, and what happens is, life becomes more colorful, richer, more interesting — you have better conversations."

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