Part-time workers with flexible schedules end up doing more work without pay.
The family-friendly hours where workers control their own schedules often end up working more after-hours the research from the University of Kent found.
On average in the UK men work an extra 2.2 hours a week in unpaid overtime. Women work for about 1.9 hours.
But Kent's Dr Heejung Chung and Dr Mariska van der Horst from the Vrije Universiteit Amsterdam, wanted to see if flexitime, teleworking or the ability to set their own hours encouraged workers to put in more unpaid overtime.
And although flexitime and teleworking did not increase overtime hours, for those who could control their own schedules worked more: professional men about an hour and women without children about 40 minutes.