The Commerce Commission and Auckland Airport's latest interactions are being seen as a sign regulation is working. 

Auckland Airport isn't lifting its airline charges for the next two years as much as intended, after the commission's report showed their targeted returns were too high.  

The report also found the airport's multi-billion-dollar infrastructure investment plan is appropriate. 

New Zealand Airports Association Chief Executive Billie Moore told Andrew Dickens the investigation is all part of the part of the process. 

She says the feedback wasn't unexpected because these processes take time.