Paid time off (PTO) is meant to be personal time spent away from work responsibilities, while still being compensated, including vacations, sick leave or even mental health days. Though policies like unlimited PTO are becoming more common, most people find it hard to disconnect from work during their time off, a new poll shows.

Fishbowl by Glassdoor, a social network for professionals, asked 20,297 professionals "Do you believe you can fully unplug from work when you take paid time off?" Over half (54%) of respondents answered no. 

Fishbowl found that the inability to disconnect during PTO varies by age and occupation. Their poll shows that only 47% of 21-25-year-olds say they can't unplug, compared to 65% of professionals aged 45 and up who say the same, likely due to the increased responsibility and experience required of them. 

Teachers were most likely to have trouble disconnecting from work, as 73% say they can't unplug. Lawyers were a close second at 71%, followed by professionals in accounting (59%), finance (55%), and consulting (51%). Tech and health care were the top industries for unplugging, with 56% of professionals in those fields saying they can unplug.

According to the report, there are several reasons why professionals can't unplug from their work duties while on leave, including toxic work culture, inadequate PTO and/or fear of delayed career advancement. 

The "always-on work culture" is especially prevalent in education, according to Sadiya Strong, a 6th grade charter school teacher who expressed the need to "get ahead" when on vacation.

"There's always something to do. You may be a week ahead, but you could always be two weeks ahead," she tells CNBC Make It. "That's one of the downfalls of teaching. Even when the work day is done, the work itself isn't."

This inability to fully enjoy PTO is something employers must discourage, according to Richard Johnson, the report author and Glassdoor associate economist, as it can be detrimental to employee retention.

"Employers must encourage employees to physically and mentally unplug from work," he said in a statement. "By not doing so, employers risk losing employees to competitors that prioritize their employees' wellbeing and recognize that PTO policies are not only a competitive recruiting perk but also a core part of eliminating burnout among their workforce."

Johnson recommends that people who are struggling to unplug try different strategies like "planning your departure and return, don't rush to return and take time off before you need time off."

A more unconventional way to make the most of your time off is finding a vacation accountability buddy. This has helped Priti Joshi, a VP at Bumble, be intentional on unplugging from work.

"There will inevitably be urgent things that show up at work and make it feel like an inconvenient time to take off. You might feel compelled to cancel your PTO," she told CNBC Make It's Jennifer Liu. "That's when it's important to have that person who holds you accountable to take your time off. They can be the little angel sitting on your shoulder reminding you it's important and good to take time away from the office."

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