McCaw has featured in safety videos, photo shoots, and has interacted with fans at promotional events.
"I look forward to continuing this next stage of my journey with Air New Zealand, starting with Buenos Aires," he said.
McCaw will travel to Argentina in December to promote Air New Zealand's Buenos Aires service as well as "destination New Zealand", while also spending some time with local budding rugby players there.
Air New Zealand chief executive, Christopher Luxon, said the airline was proud to support world class New Zealanders like McCaw.
"Richie has made a huge contribution to rugby in New Zealand and around the world and is an inspiration to New Zealanders young and old," he said.
"While it's sad we will no longer be seeing him on the rugby field, it's exciting Richie has decided to continue his close association with us as an Air New Zealand brand ambassador."
Mr Luxon said McCaw "truly embodies" the airline's can-do values, as well as also sharing its love of aviation.