Samoa Air has become the first airline in the world to introduce a 'pay as you weigh' system - charging passengers per kilogram rather than per seat.
The company claims their system is fairer than simply charging per seat, and that many families with small children are benefiting from the scheme.
Under the new move, passengers input their weight into the airline's online booking section.
Rates start from around 70p a kilogram for the total weight of the traveller and their baggage for the shortest domestic route.
The price goes up to around £2.75 per kilogram for the longer route from Samoa to American Samoa.
Pilot and chief executive of Samoa Air, Chris Langton, told ABC News: "Planes are run by seats, not by weight, and passengers should be educated on this important issue."
"There is no doubt in my mind that this is the concept of the future. We always weigh the mass that is on an aircraft... It doesn't matter whether you are carrying freight or people.
"Anyone who travels at times has felt they have been paying for half of the passenger next to them. The standard width and pitch of the seat are changing as people are getting a bit bigger wider and taller than they were 40-50 years ago."
He added that it would will raise awareness of public health and obesity issues. Speaking in The Sun, he said: "We have worked out a figure per kilo. This is the fairest way of you travelling with your family or yourself. You can put your baggage on, there are no extra fees in terms of excess baggage or anything, it is just a kilo is a kilo is a kilo.
A spokesman for Samoa Tourism said he believed the policy would also help with safety standards.
He told The Metro: "When you're only fitting eight to 12 people in these aircraft and you've got some bigger Samoans getting on, you do need to weigh them and distribute that weight evenly throughout the aircraft, to make sure everyone's safe.
The subject of charging overweight fliers more has long been a controversial issue in the aviation industry.
Last year, former Qantas economist Tony Webber suggested heavier people should pay more to fly.
He reasoned that just as people are charged for excess baggage, so people should be charged for excess weight. His rationale? The more a plane weighs, the more fuel it must burn, which costs the airline more and, in turn, will increase air fares.
And, a poll carried out by Aol Travel in response to his suggestion shows that two-thirds of people agree with him.
Over 10,000 people took part in the survey - and 71per cent agreed that people who weigh more should be charged more to fly.
What do you think? Is charging per kilo rather than per seat the fairest way to travel? Leave your thoughts below.
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