Qantas and Air New Zealand have announced a codeshare agreement on 115 domestic routes in New Zealand and Australia.

Under the agreement, Qantas will add its code on up to 30 routes on Air New Zealand's domestic network, and Air New Zealand on up to 85 Qantas domestic routes.

Bookings for codeshare flights, which exclude trans-Tasman services, can be made from the end of July for travel starting October 28, 2018.

“While the two airlines will continue to compete very strongly across all markets, Air New Zealand and Qantas are known for having a commitment to innovation, customer service excellence, operational performance and safety,” Air New Zealand chief executive Christopher Luxon said.

“We are confident that our respective customers will enjoy the reciprocal benefits on both sides of the Tasman.”

Qantas CEO Alan Joyce said the two national carriers had a lot of shared history, going back almost 80 years.

“We've been partners at various stages over that time and we have a lot of respect for them as a competitor. A codeshare deal on our domestic networks makes sense for customers because it leverages the strengths we each have in our home markets.”

The airlines said there is also the potential to explore areas of mutual interest, including research into biofuels, freight and ground-handling opportunities.