One middle-aged Kiwi filed an insurance claim of over $250,000 after they needed surgery for a brain tumour while travelling in Europe.
The medical claim topped the list for Southern Cross Travel Insurance, which is urging New Zealanders not to substitute insurance for crowdfunding.
According to company research, one in six New Zealanders travel without insurance. Meanwhile 61 per cent of New Zealanders believed it was unacceptable for uninsured travellers to seek public funding for an overseas accident or medical emergency.
Other substantial claims for 2018 included $212,000 after a person in their 60s who had a heart attack in the United States, and another travelling there in their 40s racked up $204,500 in bills after having a cardiac arrest.
The youngest in the top 10 was a pre-teen who needed surgery for appendicitis while in the United States, costing $116,000.
SCTI chief executive Chris White said he believed crowdfunding websites had led to an increasing reliance on them to substitute travel insurance.
"While it's awful to hear of Kiwis having an accident or falling ill overseas, it's frustrating to see crowdfunding pages set up afterwards when it was obvious that travel insurance could have covered the cost.
"Travel insurance is accessible and affordable when you consider the cost of going overseas, so there's no excuse to travel uninsured."
Many overseas hospitals, including in parts of the United States, required up-front payments before starting treatment. This could be problematic for someone who didn't have insurance, White said.
"On top of covering the costs of treatment, reputable travel insurers would have a 24-hour emergency assistance team that could coordinate medical treatment or evacuation, keep family members informed, provide payment guarantees and help with language barriers."
Kiwi fitness instructor Kobi Bracken racked up over $50,000 in medical bills after a near-death experience in Bali last year when she was thrown off a motorcycle in a horrific crash.
The 25-year-old was heading home for the night on the back of a motorcycle when it was hit by a van at high speed, leaving Bracken with life-threatening injuries including a snapped femur, fractured eye socket, smashed cervical spine, an exposed knee cap and extensive blood loss.
Luckily, she had travel insurance after her mum made her look into it while booking her flights, saving them tens of thousands in medical bills.
The death of Kiwi woman Abby Hartley in Bali last year highlighted the conundrum of buying travel insurance with pre-existing medical conditions.
Hartley had fallen ill with a twisted bowel while on holiday and was placed in an induced coma.
With the Hartley's travel insurance refusing to front up for hospital bills due to an undisclosed pre-existing condition, the New Zealand Government was asked for assistance, and refused.
A Givealittle page raised $230,000 in a bid to get her back to New Zealand. After she died the family donated $50,000 of the money remaining after bills had been paid to charity.
Insurance Council of NZ chief executive Tim Grafton said last year there was a range of pre-existing conditions most travel insurers will cover, and then others which a negotiation will be entered into, considering the countries visited.
"There will be a need if you do have an existing condition to tell your insurer and have that conversation," Grafton said.
"It doesn't mean you won't be insured, but possibly it may do, and if an insurer doesn't want to take on that risk, you probably want to seriously reflect on whether or not you should be travelling."