Londoners are the quickest to raise concerns about rising London Underground temperatures, a new study has found.
According to recent findings, commuters in the British capital are more likely to complain quickly about soaring Tube temperatures than their counterparts in Boston and New York.
Based on findings at Northwestern University in the US, complaints by Brits surged by 27 per cent for every degree the temperature increased above 10C.
By contrast, complaints went up by 12 per cent for each degree among New Yorkers and just 10 per cent among those in Boston.
However, while Londoners recorded the highest spike of complaints when temperatures rose, New York still recorded the most overall complaints.
Researchers suggested that this may suggest “thermal conditions in New York’s transit system are less comfortable than those in London’s”.
In their methodology, the researchers explained that they examined how commuters across the three key subway networks perceived heat at different times of day.
Scanning 85,000 posts across X and Google Reviews from 2008 to 2024, they focused on posts specifically about heat discomfort.
Addressing the findings, researchers acknowledged that: “Subsurface temperatures in the London Underground, for example, have reached 47C, surpassing London’s highest recorded air temperature [of 40.2C].”
People struggle to use parts of London’s Underground network, especially during summer, due to soaring temperatures and inadequate ventilation.
Just 40 per cent of trains on the London Underground have air conditioning, which is considered the oldest subway system in the world.
While newer trains, such as those on the Elizabeth line, are air-conditioned, it’s harder to update other parts of the network, which are sometimes very deep underground.
There are also other reasons for soaring temperatures, including packed tube carriages and even train brakes, adding to the overall heat.
Last summer, some Tube travellers complained of commutes feeling ‘like a sauna’ with temperatures inside the Underground reaching 33C in July 2025.
Data published last year also revealed which Underground lines are the hottest, with the Victoria and Central lines often predicted to have the warmest temperatures across the network.
