Female graduates are unlikely to earn the same as male counterparts in the long term - unless they go into professions relating to information systems or the performing arts.
A Ministry of Education study released this week has found tertiary qualifications make very little difference when it comes to pay parity between men and women.
A person's earnings generally increase with the level of tertiary study, but there is a marked difference between what men and women with the same qualification are paid.
The study looked at what graduates earned after one and four years of starting work.
While many female bachelor graduates earned slightly more than males one year after graduation - roughly $130 a year - things changed greatly down the track.
By the time they had been working for four years, males were earning around $47,760 while women were on $43,380 - a difference of $4380.
"It appears that there is an unequal benefit to tertiary education between males and females," said the report's author, Paul Mahoney.
When broken down by profession women working in performing arts were the only ones to earn significantly more - about $1400 a year - while those in information systems earned $10 more than their male counterparts.
The pay difference was up to nearly $8000 a year in some other professions. Female medical study graduates earned $6560 less than males, lawyers earned $4150 less, teachers $2400 less and women in communications and media earned $1730 less.
Mr Mahoney said one of the reasons men earned more than females may be link to a difference in the number of hours or weeks they work each year or the kinds of occupations and industries they work in.
"Where possible, future studies will test if this is the case."
NZ Union of Students' Associations national women's rights officer Caitlin Dunham said, "A lot of the time it's the fact that women have the risk of getting pregnant so will have to take time off. They will also be less likely to be in the line for promotion."
She said one problem was it was still "very taboo" to talk about how much you earned, while employers often placed the blame on women for not negotiating pay rises as well as men.
Equal Employment Opportunities chief executive Philippa Reed advised women to be informed about the going rates of pay and to ask for transparency when negotiating rises or promotions.
EARNINGS 4 YEARS AFTER GRADUATION
Male $53,460 Female $51,270
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