Otago University researchers estimate the deadly 2009 swine flu cost New Zealand's hospitals about $31 million.
However, they say actual cost could be more than $40 million because their study only included hospitals, not primary care and public health services.
The study's lead author, associate professor Nick Wilson, says the spread of swine flu, or H1N1, in 2009 killed 49 people, sent 1122 to hospital and 102 of those to intensive care.
Calculations estimate the average cost for those hospitalised was $17,000, rising to $97,000 for people admitted to intensive care.
The study also estimates the cost-effectivenes of providing hospital care was about $155,000 per life saved.
"This is very good value for money, especially since some of the lives saved were young people who would otherwise have lost many years of future life," Dr Wilson says.
The researchers say the indirect economic cost to society of a pandemic would probably be much higher because of effects such as lower workplace productivity.
However, "the high cost estimate from just hospital care alone in this study indicate the potential value of further work on preventative measures, such as influenza vaccination, and of investing in pandemic planning and other control measures," associate professor Michael Baker says.