Fathers who work full-time earn on average 21% more than their male colleagues who do not have children, according to a new study by the think tank IPPR and TUC.
The study of 17,000 workers found male parents receive what it is calling a "wage bonus". Fathers with two children, however, earn 9% more than their childless male colleagues.
In contrast to the "wage bonus" received by men, full-time working mothers received a "wage penalty", earning on average 11% less than childless women.
IPPR and the TUC report said the reasons behind higher pay for full-time working fathers was not clear, but cited longer working hours, positive discrimination and improved effort. Referring to figures from the Office for National Statistics (ONS), full-time working fathers work on average 30 minutes more than their childless colleagues per week. Comparatively, full-time working mothers work an hour less than their colleagues a week.
The TUC said the report's findings reflect traditional stereotypes that men are the primary earners in a family, whereas women are expected to fit in work around their children.
TUC general secretary Frances O'Grady said: "It says much about current attitudes that men with children are seen as more committed by employers, while mothers are still often treated as liabilities."