The falling New Zealand dollar and fee increases at other institutions meant Otago needed to restore relativity with its competitors, pro-vice-chancellor (international) Prof Sarah Todd told a university council meeting last week.
The main competitors were institutions in other parts of New Zealand and in Australia.
Students searching for an overseas university at which to study had "price-quality perceptions" based on factors such as a university's age, history, reputation, ranking, location, fees and the quality of its marketing.
If fees at Otago - ranked as New Zealand's top research university - were too low, a "dislocation" could occur in students' minds, she said.
She likened it to a person looking at a pair of jeans in an upmarket menswear store which were the same price as jeans from a chain store.
"If the price looks unusually cheap, they will wonder why. It is the same with a university. We are a provider of goods and services just like anyone else."
New Zealand universities were also more attractive to international students because of this country's falling dollar, Prof Todd said.
"While it is unclear how much longer we will enjoy the currently favourable conditions, the low value of the dollar means we are tracking as much as 60% cheaper on affordability matrices in some key markets compared to the same period last year."
Otago's key markets are the United States, China and Malaysia.
About 2270 international students are enrolled this year from more than 90 countries.
About three-quarters of them pay international fees, while the remainder - PhD students and students from universities with reciprocal fee agreements with Otago - pay the same fees as New Zealand-born students.
New Zealand universities must ensure international fees cover tuition costs so international students are not being subsidised by domestic students.
In the past, fee increases have been about 5% a year, but the council agreed with Prof Todd's recommendation to increase most fees by much more than that next year.
Student representative Simon Wilson voted against the increase.
Edwin Darlow abstained from voting.
Nil fee increases were adopted for two courses, with fee rises for the majority of the rest ranging from 6.4% to 21.7%.
Of the 306 courses listed, fees for 201 will rise by 10% or more.
The large fee increases only apply to international students enrolling for the first time next year.
The university guarantees their fees will only rise by 5% per annum for the rest of the time they are at Otago.
