The most common reason (24%) for working on holiday is because people feel a responsibility to reply when a colleague messages them.
Meanwhile, 18% state they get stressed if they miss things while being away and 9% fear not being viewed as a team player if they do not work on holiday.
Shakil Butt, founder of consultancy HR Hero for Hire, said employers' strong focus on productivity can encourage overworking.
Speaking to HR magazine, he said: “There is a mixed narrative emanating from most employers. On the one hand there is an ongoing focus on productivity and efficiency in an increasingly competitive market whilst simultaneously telling staff their wellbeing matters and is important to the organisation.
“This is being understood by the workers that, yes, their wellbeing matters but the work matters more.”
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The study also found one in five (18%) continue to work as normal while off the clock.
On average, those who worked while on leave spent two-and-a-half hours per day on various tasks, 48% replied to work emails or messages and 32% completed administrative tasks.
Claire Williams, chief people officer at HR software provider Ciphr, said overworking is counterproductive.
She told HR magazine: “It seems that in today's work scene, clocking off doesn't really mean stopping work for many people.
“This relentless pace is not just tiring, it's counterproductive and could have a big impact on an individual’s health and wellbeing (and stress levels), as everyone needs to be able to disconnect from work and relax.”
The study found 14% of UK workers have previously worked on Easter Sunday, 13% have worked on Boxing Day, while 11% have worked on Christmas Day.
Hybrid and remote workers are more likely to work while on leave (64%) compared with office-based workers at 44%.
Kevin Pratt, editor at Forbes Advisor, said remote working can promote an expectation of constant availability.
He said: “The workplace has changed massively over the last few years, including the rise of remote working, but it seems many employees still face the pressure of being ‘always available’.
“As Christmas approaches, it is important to manage your workload effectively and set expectations with your manager, and to have the time off you need to reset.”
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Williams said employers need to create a culture where rest is seen as necessary and productive.
She said: “HR teams need to be clear about work boundaries and foster a workplace culture in which taking a break is actively encouraged. Managers play a key role too, as they need to reassure their teams that it's absolutely okay, necessary even, to step away from work after hours.
“And finally, the C-suite needs to lead by example, as valuing rest and downtime is key to creating a more balanced, healthier work environment. It's all about working smarter, not just harder, and recognising that a well-rested team is a more effective one.”
Butt added that as the year ends, employees should be able to take their total annual leave allowance.
He said: “At this time of the year, many line managers, prompted often by HR, will be having conversations about annual leave not taken during the year and negotiations over how much can be carried forward to the following year without being lost.
“This is often one of the key indicators that staff are being overworked but it is often not limited to one tier of the organisation, but problematic across all parts, symptomatic of the inherent culture.”