The airport sold the exclusive rights to four taxi spaces outside the terminal, effective as of July 1 this year, and has now asked for registrations of interest for the remaining three.
Airport chief executive John McCall said it was common for airports around the country to sell rights to taxi ranks.
"This practice of exclusive ranks is done at many airports and is tested by the Commerce Commission as well."
Otago Regional Taxi Federation representative and Dunedin Taxis director Murray Alcock said he was disappointed with the way the airport had gone about the process.
Dunedin Taxis had put in a "substantial" but unsuccessful offer for the first four spaces and was considering how much it could put in for the remaining rank, he said.
"At the end of the day, it is the customer that will pay."
The price of a taxi fare from the airport to the centre of Dunedin is now about $80.
Mr McCall said the airport was only asking for registrations of interest for the last three spaces because of "issues" that had been raised by taxi operators who shared the remaining three spaces.
"I am not prepared to talk about those [issues], but it is all about competition between taxi operators.
"We have asked the taxi industry for proposals on how that should operate and there is the opportunity for them to bid for exclusivity on that as well," Mr McCall said.
Other businesses at the airport paid for their space and it was no different than charging planes to land or the higher overheads rental car companies had to pay to operate at the airport, he said.
Mr Alcock said the airport was "just trying to gouge the public and the taxi companies for more money".