Working New Zealand mums are taking home an average $5 less per hour than working fathers, figures from Statistics New Zealand have revealed.
The gap between the average father's wage of $28.30 per hour and a mother's average $23.40 shows a 17 percent wage gap.
While the gap between men and women without children is reduced to just five percent, the figures show working parents are better off than their childless colleagues.
"Mothers with dependent children earn more than $23 an hour, on average, almost $1 an hour more than men and $2 more than women without children," insights manager Stephen Oakley said.
Research shows that mothers may get less because they spend more time caring for children, which interrupts full-time paid work and which may reflect breaks from work and reduced work experience.
Green Party women's spokeswoman Jan Logie says the gender pay imbalance needs a commitment from the Government to ensure every woman is paid what she is worth.
"When women are underpaid it has a real impact on their partners and children, and the life they're able to create together," she said.
"Any new pay equity legislation needs to be introduced before the election so that voters can see what the National Government stands for."
Ms Logie has a member's bill in the ballot that would require employers to produce a transparent pay gap index for their company.