The 10 least polluted cities in the world in 2025

Pollution is inextricably linked to global warming, as well as to the well-being of the population. Science says so, and the fact that it’s still rarely discussed is certainly no reassurance. In some areas of the world, unbreathable air—like unclean water—represents one of the primary risks to health and, consequently, to the quality of life. And very often, it’s precisely the cities that suffer the most in this regard, burdened by traffic, uncontrolled construction, and excessive population density.

But, amid all these realistic problems, which are the most virtuous? Are there cities heading in the right direction, giving concrete meaning to the adjectives "green" and "smart"? The answer is yes, and they are mostly concentrated in areas where there is the economic resources, the right policies, and the real will to change things.

Northern Europe wins hands down, demonstrating once again what a beacon of excellence and a virtuous example to follow.

This is confirmed by the constantly updated rankings from the Numbeo portal, which collects objective data (statistics from the World Health Organization and other authoritative institutions) and subjective data (user and citizen ratings on air and water quality, etc.) and cross-references them to create a fully-fledged ranking that is updated periodically and in which the top performers are inexorably outperforming the rest.

The research includes 328 centers spread across every continent. Here, then, are the 10 cleanest and least polluted cities on the planet.

10) Hobart, Australia

In tenth place is the only city outside Europe in our ranking: Hobart, in Australia. This city stands out for its clean air and pristine landscapes, and local green initiatives are more closely linked to nature conservation and sustainable tourism. It’s not an "overbooking" destination—although those who travel to Australia usually make a stop here—and therefore doesn’t require drastic measures. However, the city continues to enhance its unique ecosystem by protecting coastal areas, supporting forest management, and promoting environmentally friendly tourism practices.

This approach still guarantees a high quality of life today, with livable green spaces and opportunities for outdoor activities. The geography certainly helps, but Hobart’s preservation of local nature clearly highlights the path to earning a place among the least polluted cities.

9) Luxembourg (city), Luxembourg

Luxembourg is strongly committed to sustainability: in June 2025, the Climate Nexus Framework Convention was signed, a five-year initiative (2025-2030) with the University of Luxembourg to make the country "climate-ready" by integrating research, education, policies, and public engagement. Furthermore, a campaign, reNature, was launched to promote the use of "green facades"" in urban areas and promote biodiversity in the city.

And that’s not all: the Environmental Implementation Review Country Report was also published in June, which takes stock of the state of the environment and current policies. The result? A mix of research, action, and urban beauty that maintains a high quality of life.

8) Gothenburg, Sweden

Gothenburg is a European model of urban sustainability. Its waste management strategy currently targets a 30% reduction in waste per capita. At the same time, it aims to reduce the climate impact of construction and non-food purchases by 90% by 2030 compared to 2020, promoting a comprehensive circular economy.

From a governance perspective, it hosted the Gothenburg Sustainability Summit in 2025, a forum for leaders and innovators on the road to a sustainable future. Furthermore, the tourism sector has participated in discussions such as the Rhodes Forum to accelerate the decarbonization of travel and tourism. A concrete, participatory vision that makes the city livable and cutting-edge, as our ranking demonstrates.

7) Eindhoven, Netherlands

Eindhoven has been working for years to create a cleaner and more livable environment. A project called Stadsdommel protects and enhances green spaces along the Dommel River, creating natural paths for walking and relaxing in the city. In 2025, the city also intensified its controls on corporate sustainability: 85% of inspected companies had to adopt additional measures to comply, confirming that truly low-pollution cities require political support and oversight.

Eindhoven is also part of the Brainport innovation district, committed to clean energy with research and development on batteries, hydrogen, and renewable sources. Together, these actions strengthen air quality, green innovation, and urban livability—three key aspects of pollution management.

6) Tallinn, Estonia

Tallinn shines for its ecological innovation and long-term vision. Its national celebration, Song and Dance, has become zero-waste, winning the coveted ITB Earth Award 2025. It has also applied to become Estonia’s first zero-waste city, opening a circularity center in October 2024 and planning additional hubs by the end of 2025.

At the same time, Tallinn is adopting the 15-minute city model to make all daily services accessible quickly (15 minutes, to be precise). Not to mention that, like many other Nordic cities, its climate plan aims to reduce emissions by 40% by 2030, with measures on free public transport and building efficiency. A city that already thrives on sustainable tourism and aims to become an increasingly cutting-edge, "compact" and efficient melting pot for its residents as well.

5) Stockholm, Sweden

In fifth place, we return to Sweden, the capital. Stockholm launched an ambitious Climate Action Plan 2030 in 2025 to accelerate decarbonization, abandon fossil fuels, and build a resilient and climate-positive future.

Furthermore, the Stockholm Wood City project, one of the largest solid wood urban settlements in the world, is taking shape. Construction is scheduled to begin in 2025 and be completed in 2027. It will offer sustainable homes, offices, and commercial spaces, benefiting air quality and people’s well-being. Together, these initiatives confirm Stockholm as a green, innovative capital that cares about quality of life.

4) The Hague (Den Haag), Netherlands

The Hague aims to become CO₂ neutral by 2030 with concrete measures. It is expanding zero-emission zones, strengthening sustainable mobility, public transport, and green spaces, while discouraging the use of natural gas and any other fuel.

A symbolic but powerful step: in 2025, a law came into force that bans advertising for fossil fuels (gasoline, air travel, cruises) in public places—a world first. This legislative move is seen as a global example of integrating communication and climate strategy.

3) Vienna, Austria

The Austrian capital takes the top spot. Vienna is active on multiple fronts for sustainability. The Vienna Climate Act, a pioneering law that includes mandatory climate impact assessments (such as the "Climate Check") for urban planning and policy interventions, is expected to be adopted by 2025. This represents a first step toward becoming "climate-neutral" by 2040.

Furthermore, on June 3, 2025, the city hosted the Austrian World Summit, an international climate conference with the slogan "Unite in Action – Terminate Pollution," promoted by the Schwarzenegger Climate Initiative. Other events, such as the symposium "Designing Green + Resilient Cities" and the permanent climate exhibition at the Technisches Museum, also underscore its drive toward green, climate-conscious, and resilient cities. In short, it could become a driving force for Central and Southern European cities in the coming years.

2) Reykjavik, Iceland

The silver medal goes to Reykjavik, one of the cleanest and greenest capitals in the world. Much of the credit goes to the massive use of renewable energy: approximately 85% of consumption is covered by geothermal and hydroelectric power. This has allowed the city to maintain extremely high air quality, with AQIs often below 10. The city has launched a Climate Action Plan 2021–2025 to reduce emissions and aims for carbon neutrality by 2030.

On the urban front, the Master Plan 2040 prioritizes electric public transport, bike paths, and pedestrian spaces, reducing private traffic and making the city more livable. Symbols of architectural sustainability are undoubtedly the geothermally heated Harpa Concert Hall and the Marshall House, an example of creative reuse. Reinforcing this commitment, events like Reykjavik Green Days involve citizens and businesses in concrete ecological practices. A sort of ongoing challenge to defeat pollution.

1) Helsinki, Finland

Helsinki tops Numbeo’s ranking as the least polluted city in the world. It’s no coincidence that it’s the capital of Finland, voted the happiest country in the world for the eighth consecutive year in 2025.

Helsinki is a paragon of sustainability: in 2025, it was the first major city to receive the GSTC Green Destinations certification, a recognition that recognizes tourism and sustainable urban management. According to the Global Destination Sustainability Index, it ranks first worldwide for environmental performance and local management.

Helsinki is also a "green and blue" city: 70% of its territory is covered by forests and water, and its tap water is among the purest in the world. It boasts 1,200 km of cycle paths, increasingly electrified transport, and even autonomous bus testing. With pristine landscapes, sustainable design, and quality services, Helsinki embodies the perfect idea of a clean, happy, and cutting-edge city. The statistics also confirm it.

Original article published on Money.it Italy. Original title: Le 10 città meno inquinate al mondo nel 2025