The additional three flights will operate on the Singapore-Christchurch route between November 19 to February 16.
The new services will leave Christchurch Airport on Monday, Wednesday and Friday. They will add 759 more seats a week to the route, Singapore Airlines general manager New Zealand George Robertson said.
The A350-900 flight to Christchurch has 42 business class seats, 24 premium economy and 187 economy seats.
The flight will arrive in Christchurch at 12.50pm (NZT) after departing Changi Airport at 10pm (SGT). It will depart Christchurch at 2.20pm and arrive in Singapore at 8pm.
Some of the additional flights are on sale from today.
Emirates already operates daily flights into Christchurch on its Airbus A380.
But at this stage, Singapore Airlines' 471-seat, double decker A380 will only fly into Auckland when it returns from November 22. The aircraft will replace the A350-900 and add 1526 more seats a week to the Auckland-Singapore route.
Singapore Airlines has not operated its A380 in New Zealand since the start of the Covid pandemic in March 2020.