The council, along with the student associations of University of Otago and Otago Polytechnic, are trialling the discount until the end of April.
As part of the trial, students of both organisations and Aoraki Polytechnic also received a free GoCard as an incentive.
Cr Michael Deaker said at a committee meeting last week there had been a ''surge'' in student patronage of the bus system.
In the first 22 days of the trial, 18,223 student trips were recorded as using the bus service, and it appeared to be stabilising at that level, he said.
The most popular routes were those from Normanby, Opoho, Balaclava and Kenmure.
Given the council was having to review its bus services, it needed to be mindful of the ''dramatic'' change in the population of bus users.
''We don't want anything to deter this very encouraging trend,'' he said.
Communications manager Peter Taylor said the council had received a tweet from a student saying they had saved $110 due to fare discount.
Otago University Students' Association president Ruby Sycamore-Smith said the association was really happy with the numbers and hoped students would continue to use it regularly.
Feedback was that it was mostly local Dunedin city students and older students who used the service, as they lived further afield.