Wellington's regional council is paying $150,000 a month to add extra buses to its ailing new network.
It has also spent $338,000 between July and September on contractors to help embed the new network, which has been riddled with problems since it launched in July.
Since then commuters have complained of overcrowded buses, buses not showing up at all, and the new routes causing inconvenience.
The regional council was using what it called 'banker buses' to supplement capacity on four routes that travelled between Lyall Bay and the city, Karori and Seatoun, and Johnsonville and the city.
Those buses cost the council $108,000 a month.
It was spending $41,000 a month to extend route 18 to link Miramar to Karori.
Eventually the buses would become a permanent part of new timetables, but the council would continue to pay for them, councillor Daran Ponter said.
"So the $150,000 that we may be paying now ... gets incorporated into the overall network, and that's the sort of amount of money we would continue to pay into the future."
Mr Ponter said on the four routes with banker buses, which were all run by NZ Bus, there was a bigger demand for buses than the council had expected.
Banker buses were being used because, in part, buses there were not the right size were being deployed, he said.
When 17 double-deckers for NZ Bus arrived in December or January, they would help ease pressure on those routes.
In September it was revealed people were being left behind on a busy NZ Bus route because buses were too small.
The extra money was coming from a transport reserve fund, but the spending would have to be added to annual plans from next year.
The council had saved money through the tender process for the new bus contracts, Mr Ponter said.
"But we have to acknowledge that there are capacity issues to address, no councillor, no council, likes to go to ratepayers to say they require more money for a service, but the flip side to this is to do nothing, and that's not tenable either."
The council always planned to fill any gaps in the new service if it needed to, he said.
The council had spent $338,053 on contractors between July and September.
It said it always intended it would need to employ additional specialist resources to assist with the transition to the new bus network, the bedding in and resolution of issues.
A National MP who was based in Wellington, Nicola Willis, said putting extra buses on was a good step, but the council did not have a choice.
"They have to do it, because Wellingtonians deserve a reliable effective bus service, but this just goes to show the council should have listened to Wellingtonians in the first place.
"They should have consulted properly, they designed the routes poorly and now Wellingtonians are having to pay the price not just through the poor bus service, but with a lot of ratepayers money going into the fix."