Auckland International Airport carried out a major review of its capital structure in 2013.
That process culminated in $454 million being returned to shareholders last year and an associated re-leveraging of the firm's balance sheet.
To finance the share buyback, the company undertook over $1 billion in successful debt financings in both the domestic and international markets.
The judges said those transactions significantly lowered the cost of capital for the organisation and optimised tax efficiency.
AdvertisementAdvertise with NZME.
"Auckland International Airport demonstrated, in the process, both innovation and best market practice."
The company's chief financial officer, Simon Robertson, said the review and its outcomes had provided a great result for the airport's shareholders.
Fonterra and HRL Morrison & Co-Infratil were the other finalists.