More than a third of Air NZ seats expected to be filled by Australians, who lost a direct service in April.
Air New Zealand's flights to Buenos Aires will be more than a third filled with passengers from Australia, an analysis of the service says.
Capa Centre for Aviation says the "bold" move into Latin America next December has been made possible by a new partnership with Aerolineas Argentinas, which will provide connections within South America and local sales support.
"For Air New Zealand, Buenos Aires fills the last major white spot in its network following the upcoming resumption of services to Singapore.
"Argentina has proven to be a challenging market for foreign carriers but for Air NZ it represents the best South American option with a risk level that is acceptable with the right partnerships," Capa says.