Sunburn, bug stings, trips and falls, and run-ins with the barbie hotplate cost hundreds of millions of dollars in injury expenditure each summer.
Over the past five years, the Accident Compensation Corporation has spent $3.4 billion paying for the treatment of unsuspecting Kiwis coming a cropper between December and February.
And those costs are rising by about $50 million each summer.
ACC head of injury prevention Isaac Carlson said summer's extra days off and good weather drew Kiwis like moths to beaches, campgrounds, sporting fields and out to their own gardens after a long winter under cloudy skies.
"During the summer holidays people tend to relax and change their regular routines and - while some might say that's how accidents happen - the truth is that most injuries are preventable," he said.
He warned Kiwis to take a minute this summer to think about the risks before jumping into an annual cleaning of the backyard or their favourite outdoor pursuit.
This was particularly the case when up a ladder at home, riding a bicycle, playing sport - or doing any activity where you might lose your balance and fall.
Falls were the most common cause of injuries with 122,475 people hurt this way during the 2017 summer at a cost of more than $100m.
Kiwis were also regularly hurt when slipping, twisting and straining to lift heavy objects, while soft tissue sprains, scratches and broken bones were the most common types of injuries.
There were 525 reports of people injuring themselves around the barbie last summer, with claim costs totalling $482,219.
Insects inflicted 11,745 bites and stings, leading to claims totalling close to $1m, while 25 people suffered sunburn and billed the taxpayer $6706 to cover their treatment costs.
There were almost 4000 injuries around beaches, rivers and lakes last summer at a cost of more than $2m.
But Surf Lifesaving national lifesaving manager Allan Mundy said this figure might not be as high as it appeared, given about 59 per cent of the population visited a beach last summer.
Aside from performing 1500 life-saving acts last year, he said lifeguards helped plenty of people with severe sunburn after dozing off on the sand. Skylarking beach-goers blowing out a knee after backflipping from the dunes was another regular, he said.
Lifeguards also occassionally helped young kids with severely burned feet from jumping into covered-over fire pits that had embers still smouldering from a fire the night before.
Another danger was people driving four-wheel drives on beaches and rolling them, Mundy said.
Elsewhere, the owner of a popular Coromandel holiday park said regular summer injuries included kids finding creative ways to crash new bicycles, fishhooks snagging body parts and campers hammering their fingers instead of tent pegs.
But the worst injury last summer took place when a dad badly dislocated his shoulder and had to be choppered to hospital, he said, after trying to prove to his youngsters he still knew how to body surf in the waves.