The Otago Regional Council is cutting back its bus timetable in Dunedin and Queenstown to reduce cancellations and improve reliability.
Transport manager Doug Rodgers said there were not enough drivers to operate all trips daily.
"The move will mean some reductions to the service but should mean far fewer cancellations and allow for a more reliable service for passengers," he said.
"Bus operators have been working hard to maintain a workable service, but the new wave of Covid and winter illness has created a shortage of drivers in both Dunedin and Queenstown and this, coupled with the national shortage of bus drivers, is impacting the ability to deliver a full service. "
The new timetable will come in from next Tuesday and will be the same seven days a week in Queenstown.
In Dunedin, the reduced timetable will operate on weekdays with normal weekend services running.
The updated timetable will be on the council's website, on the Transit App and the e-stops at the Dunedin Hub from Wednesday, but passengers are urged to check for alerts before setting out on their trip
Rodgers said the council had worked to maintain provisions at key times as much as possible.
"We have reviewed timetables with our transport providers to ensure our school services remain operational."
The council would update its website on Wednesday so passengers could plan their journey in advance.
Those who used the subsidised Total Mobility Services should be aware that drivers would become unavailable at short notice, the council said.
"Total Mobility users are asked to contact their personal support networks to make a travel plan should their Total Mobility taxi be cancelled."