Nearly half of New Zealanders work more than eight hours a day and almost half take their work home with them, according to a survey.
Regus, a provider of flexible workplaces, surveyed more than a million business people and asked about their work habits.
The aim was to provide a "state of the nation" picture of the pressure on workers around the world.
It found that 36 per cent of workers in New Zealand work between nine and 11 hours a day, compared with a global figure of 38 per cent of workers in the same situation.
The hardest workers in the world are those in Brazil, who spend 11 hours or more at work each day.
In New Zealand, 46 per cent of workers take tasks home at the end of the day to complete.
South Africa was the most common country for this practice, with 58 per cent of the workforce taking work home.
Professor Peter Boxall, associate dean of research at the University of Auckland Business School, said advances in technology were to blame for the growing work week.
"Information technology has definitely broken down the barriers of the place of work you go to and your home and that's a serious problem now, I think," Professor Boxall said.
The concern of work-overload was raised in the survey findings, which said it could damage both the workers' health and the productivity of the business. Teachers, journalists, lawyers, accountants, consulting engineers and academics were all "classic cases" of professionals who worked long hours and took work home, Professor Boxall said.
"A lot of it is personal choice - they choose to keep following their email ... they're often willing workaholics."
He said the danger was losing the work-home life balance, which could strain personal relationships.