Green initiatives increase support for air travel taxes
A new CBS study shows that it is easier to gain support for air travel taxes when the revenue goes towards green initiatives. Those who fly the most are also among the most sceptical about higher taxes
Many Danes are currently preparing for the autumn break. Copenhagen Airport expects around 1.1 million passengers over the holiday period.
A passenger tax has been levied on flights departing from Denmark since January 2025. The revenue helps fund both greener aviation and an increase in the annual supplement for low-income pensioners known as the ‘ældrecheck’.
How the revenue is used matters to whether people support taxing air travel. In a new Danish experiment, an air travel tax received greater support when the revenue was earmarked for green initiatives than when it went into the general state budget.
“If the political objective is to maximise support for the tax itself, our evidence suggests that a clearer and more visible link between the tax revenue and green investment is likely to help more than emphasising its contribution to general welfare spending,” says Alice Pizzo, Assistant Professor at CBS.
She conducted the study with Kristian Roed Nielsen and Kristian Steensen Nielsen from CBS. It is published in the journal Energy Research & Social Science.
How the revenue was spent made a difference
Participants in the experiment repeatedly chose between two proposals for an air travel tax. They also rated how much they supported each policy proposal. The researchers varied the tax level, how the revenue would be used and whether frequent flyers would pay an additional levy.
Earmarking the revenue for green initiatives was one of the policy features that most clearly influenced these choices. Participants were more likely to choose proposals with green earmarking, even when the researchers accounted for the tax level and an additional levy on frequent flyers.
When the revenue was earmarked for social welfare instead, the researchers found no statistically significant increase in support compared with allocating it to the general state budget.
However, this does not tell us what participants think about using the passenger tax to fund the ældrecheck, Alice Pizzo stresses. In the experiment, social welfare was described as a broad category. The ældrecheck was not included, so the study cannot show whether support would increase if this use of the revenue were removed.
The findings offer insights into what can make an air travel tax more acceptable, but they are not an evaluation of the Danish scheme. The political agreement allows policymakers to review the tax rate in 2027.
“There is a clear political tension here. Some of the people whose behaviour these policies are intended to change may also be among their strongest opponents” Alice Pizzo
Assistant Professor at CBS
Frequent flyers are the most sceptical
The more often participants flew, the less they supported taxing air travel. They were particularly sceptical about higher taxes and an additional levy on frequent flyers. Participants with high incomes were also less positive about proposals involving higher taxes.
“There is a clear political tension here. Some of the people whose behaviour these policies are intended to change may also be among their strongest opponents,” says Alice Pizzo.
She points to self-interest as a possible explanation. For someone who often flies on holiday or to visit family and friends, a higher tax could mean greater expenses or fewer trips.
“This seems to be consistent with self-interest, but our study establishes the relationship, rather than the psychological mechanism behind it,” says Alice Pizzo.
The researchers also examined whether the result was driven by a small group who flew unusually often. They removed the 5% of participants who flew most frequently from the analysis. The relationship between frequent flying and low support was almost unchanged.
Information changed which tax people preferred
The researchers also tested whether greater knowledge of the climate impact of flying could make a difference. Half the participants were shown an infographic comparing the carbon footprint of air travel with that of other activities. It also showed that a small group of travellers accounts for a large share of emissions.
The researchers found no statistically significant increase in overall support for air travel taxes or in acceptance of higher taxes. However, participants who had seen the infographic were more likely than the other participants to choose a proposal in which frequent flyers paid more.
“The information didn’t persuade people that they wanted higher air travel taxation overall. Instead, it seems to have changed their view of what a fair aviation tax looks like and who should bear more of the burden,” says Alice Pizzo.
People can therefore remain sceptical about an air travel tax while also believing that, if one is introduced, those who fly often should pay more.