Employers are getting more than £18 billion worth of free work because British workers are not taking all their holiday entitlement.
New findings reveal that only 77 per cent of people take the annual leave to which they are entitled.
And when they do take a holiday or get away from the office, they are still likely to do some work, says the UK Annual Leave Survey of more than 2,000 staff by workplace review website Glassdoor.
The UK law requires almost all employers to give 5.6 week' paid holiday per year. By only using a portion of their holidays, Brits are effectively working for free for approximately six days a year.
According to Wednesday's employment data, 30.4m people in employment in the UK earn an average of £474 a week. This means that companies are gaining more than £18bn of work for free each year, reports the Daily Telegraph.
The research also revealed that people aged 16 to 24 are least likely to take all the days off they are due.
Joe Wiggins, senior jobs community manager at Glassdoor, said: "While there is always work to be done, employees should be conscious of using time off they've earned to recharge. In turn, employers should consider being more clear to everyone about what it means to be on holiday, actually let others be on leave, and go beyond just encouraging employees to use time off."
According to Wiggins, businesses can benefit from making staff take their holidays. "Some real rest and relaxation will help employees return to work energised, ready to contribute and make them less susceptible to burn-out," he said.
The research also revealed that - surprise surprise - employees have difficulty switching off from work while on holiday and often end up doing some work when they are off because their colleagues or boss contact them. According to HR magazine, people aged 25- to 34-years old have the hardest time mentally distancing themselves from the workplace.
In total, 44 per cent of respondents admitted to doing some work while on holiday. The Scottish are the most likely to do this, with 57 per cent saying they work while away. Welsh people do the least work while on holiday, with only 25 per cent reporting that they carry on with work tasks.
Eleven per cent do so because they fear falling behind. This is the most common reason, closely followed by those angling for a pay rise and then employees who felt no one else could do their jobs.
Eight per cent believe "working is better than not working", so continue to work while on holiday, and one in 50 confessed that they work on holiday because they are afraid of losing their job.
According to Wiggins "the lines between home and work life are increasingly blurred". "With a culture of 24/7 communication, it's inevitable people will be taking work home and away with them," he said.
Calculate your leave entitlement here.
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