For the many roles they play as housekeepers, chefs and chief executive officers, stay-at-home mothers in Canada would earn about $126,593 a year if they were on a company payroll, a Mother's Day study says.

The annual study, now in its eighth year, was conducted by Salary.com, a Massachusetts-based company that assesses workplace compensation. The study said that moms who work outside the home, meanwhile, would be paid $74,101 for their home and family responsibilities in addition to their work salaries, the company said. Their at-home pay would be less because they spend fewer hours working in the home.

'I think a lot of people think we sit at home and have a lot of fun and don't do a lot of work.'—Samantha Russell, stay-at-home mother

By comparison, the study found that American mothers who work in the home would earn $116,805 US and mothers who work outside the home would receive $68,406 US. In 2007, the study found that stay-at-home dads in the U.S. would be paid an annual salary of $128,755 and working fathers would earn about $72,082.

Samantha Russell, a stay-at-home mom in New Hampshire, said the survey shed light on the important roles mothers play.

"I think a lot of people think we sit at home and have a lot of fun and don't do a lot of work," said Russell, a former pastry chef and mother of two boys.

"But they should try cleaning their house with little kids running around and messing it up right after them."

The salary calculation for mothers also took into account the roles they fulfill as laundry machine operators, computer operators, facilities managers, van drivers and janitors. With overtime work averaging about 54.4 hours a week, stay-at-home mothers worked a hefty 94.4 hour workweek.

Meanwhile, moms who worked outside the home worked an average of 54.6 hours in addition to their regular jobs.

The company surveyed 18,000 mothers about their roles and responsibilities and cross-referenced these activities with job descriptions and salary scales.