Nearly half of UK managers work at least one extra day of overtime per week, according to new research.

Almost two thirds of workers feel under pressure to put in the extra hours, with 13% working two days of overtime each week, the study by the Institute of Leadership and Management (ILM) found.

Heavy workloads and more time spent checking emails on smartphones are major contributors to working overtime, leaving 94% of managers working above their contracted hours each week.

The report also revealed that 76% of workers frequently work late, while almost half often work through their lunch break, and 38% work at weekends. Just 13% feel they have a good work-life balance.

Charles Elvin, ILM chief executive, said that it is becoming apparent how widespread the extra hours culture is within UK business.

“Excessive hours are not sustainable – there are only so many times you can burn the midnight oil before your performance, decision making and wellbeing begin to suffer.

“This is why it’s so important for organisations to equip staff with the fundamental planning and time management skills they need to cope with their workloads more effectively.”

Smartphone technology has also added to the demands placed on workers, with 86% regularly checking their work emails on evenings and weekends, and 21% accessing their email more than 10 times per day outside office hours.

Elvin warned this “obsessive checking” of email when out of the office could lead to “unhealthy behaviours”.

“We all know how stressful it can be to receive an urgent late night email when you feel compelled to respond immediately,” he added.

“Organisations can help address this with some clear guidelines on email etiquette, including when best to send and reply to important messages.”