Air NZ $4 fares sold out in minutes

Wellington airport is investigating extending the runway by 350m in an effort to attract long-haul flights to the capital.

More than 100 Air New Zealand $4 flights were snapped up within minutes by keen domestic travellers this afternoon.

The airline's Grabaseat website had flights one-way flights between Auckland and Gisborne, Blenheim and Christchurch, Wellington and Christchurch and the capital and Napier.

The seats sold out within minutes, an Air New Zealand spokeswoman said.

"New Zealanders have been snapping up great deals through Air New Zealand's Grabaseat for nearly 10 years now with our team putting several thousand of our cheapest domestic and international fares into the market every week," she said.