The top 10 green cities in the world

A green city is a city that cuts its environmental impact through clean energy, public transport, green spaces, and efficient buildings. As global urbanisation continues to accelerate, the integration of nature into city planning has become a critical indicator of a metropolis’s future viability, and a green city is no longer defined merely by its number of parks, but by its systemic commitment to environmental stability, energy efficiency, and the well-being of its residents. The greenest city in the world depends on the ranking method: in the Green City Index from Reinders Corporation, Vancouver ranks first and Oslo second, and both feature in our list. In this article, we examine the world’s leading green cities that are successfully transitioning from traditional concrete landscapes to resilient, nature-positive urban centres. 

The success of these urban trailblazers provides a blueprint for how large-scale nature-based solutions can be adapted to the most densely populated environments on Earth. By prioritising biodiversity and reducing their collective carbon footprint, these cities demonstrate that economic prosperity and ecological health are not mutually exclusive. Understanding these models of sustainability allows individuals and organisations to recognise their own role in supporting the transition toward a greener, more sustainable global future.

Here, we have compiled a list of the top 10 green cities in the world, updated for 2026.

1. Copenhagen, Denmark: Known for its bike-friendly streets and its climate ambition, Copenhagen has long been considered one of the greenest cities in the world.

Copenhagen once aimed to be carbon neutral by 2025. In 2022, the city dropped that goal after cutting its CO₂ emissions by 80%, because the waste-to-energy plant it relied on could not get funding for carbon capture technology. Its Climate Strategy 2035, in effect since January 2026, now targets climate positivity within the city's boundaries by 2035. The city continues to increase the use of renewable energy sources and green transportation options such as bicycles and electric cars.

2. Amsterdam, Netherlands: Amsterdam is another city that prioritises sustainability and green transportation.

The city is famous for its cycling culture, and its network of bike lanes and waterways makes it easy for residents and visitors to get around without relying on cars. Amsterdam aims to cut its emissions by 60% by 2030 and reach climate neutrality by 2050, but analysis by CE Delft projects a 46% cut by 2030, so the city needs to move faster.

Read more: Industries with the biggest nature footprints and what their decarbonisation looks like

3. Frankfurt, Germany: Frankfurt is working towards climate neutrality by 2035, a target its city council set in 2022, earning it a spot among the top green cities in the world.

The city's U-Bahn and trams run on green electricity, and Frankfurt is switching its bus fleet to battery-electric and hydrogen drives, with a fully alternative-drive fleet planned by 2033, according to the city's public transport body, traffiQ. It also boasts a number of green buildings, such as the headquarters of the European Central Bank, which exceeds Germany's 2007 energy saving standards by 29%, according to the ECB.

4. Vancouver, Canada: Known for its stunning natural setting and commitment to protecting the environment, Vancouver is one of the greenest cities in North America.

Vancouver's Climate Emergency Action Plan aims to halve carbon pollution by 2030, from 2007 levels. Emissions were 12% below 2007 levels in 2022, and city staff have said that even the best case would fall short of that goal, according to Global News. The city has been implementing a number of initiatives, such as expanding its network of bike lanes, to help close that gap.

5. Portland, United States: Portland has a long-standing reputation as a green city, and for a good reason. The city has a strong focus on sustainable transportation and has implemented a number of initiatives to promote the use of public transit, biking, and walking.

Additionally, Portland has been working to increase the amount of green space in the city and to protect its natural ecosystems. It aims to halve emissions from 1990 levels by 2030 and reach net zero by 2050. Emissions were 26% below 1990 levels in 2023, and the city says it needs to move faster, according to the City of Portland.

Read more: The hidden strength of nature-based credits in corporate decarbonisation strategies

6. Singapore: One of the greenest country-cities in the world, Singapore has a very ambitious target to become a 'City in Nature' by 2030.

Singapore has made investments to enhance biodiversity in the country, improve air and water quality, and combat changing environmental conditions. The government also invested in sustainable housing, transportation, and waste management solutions. Under its Green Plan 2030, Singapore aims to plant 1 million more trees by 2030 and put every household within a 10-minute walk of a park. By March 2026, around 855,000 trees had been planted, according to the National Parks Board.

Read more: Reduce, reuse, recycle: 7 ways for businesses to reduce waste

7. Zurich, Switzerland: Known for its high quality of life and picturesque setting, Zurich is also a leader in sustainable urban development.

Zurich's voters decided in 2022 that the city must reach net-zero direct greenhouse gas emissions by 2040. The city reports that it is on track, with direct emissions of 2.2 tonnes of CO₂e per resident in 2024, according to its 2025 interim report. It has also been working to promote sustainable transportation options such as trams, buses, and trains. Additionally, Zurich has been preserving and restoring its local ecosystems, making it a particularly green city.

8. Oslo, Norway: Oslo's goal is to be a zero-emission city by 2030, with a target of cutting greenhouse gas emissions by 95% from 2009 levels. Direct emissions were 30% below 2009 levels in 2023, and the city acknowledges a gap to its target, according to its Climate Budget 2026. The city has invested heavily in electric cars, and nearly all new cars sold in Norway are now electric: 95.9% in 2025, according to the Norwegian Road Traffic Information Council.

Additionally, the city has implemented a number of measures to encourage sustainable transportation, including bike lanes and pedestrian-friendly streets. Oslo also aims to make all public transport emission-free by 2028, as part of its electric bus roll-out.

Read more: Balancing portfolios: Nature-based vs renewable carbon credits

9. Reykjavik, Iceland: Reykjavik is one of the most sustainable cities in the world, thanks to its use of geothermal and hydroelectric energy.

The city's electricity and district heating come almost entirely from renewable sources, according to IRENA and the utility Veitur. Reykjavik also encourages sustainable transportation: road traffic is its biggest source of emissions, and its Climate City Contract sets out 15 actions to reach carbon neutrality by 2030.

Additionally, the city has implemented a number of measures to promote energy efficiency, including insulating buildings and using LED lighting.

10. Curitiba, Brazil: Curitiba is a leader in sustainable urban planning and public transportation. The city opened the world's first bus rapid transit system in 1974, a model now used by about 200 cities, according to the International Association of Public Transport.

Curitiba is now renewing its system: a transport tender published in August 2026 provides for 250 electric buses between 2027 and 2031, according to Diário do Transporte. Curitiba also has a number of green spaces, including parks and gardens, which help to improve air quality and mitigate the effects of changing environmental conditions. Additionally, the city encourages recycling and composting and has implemented a number of measures to promote energy efficiency.

Read more: Carbon footprint offsetting strategies: How leading companies neutralise their emissions

Frequently asked questions

What is a green city?

A green city puts nature and sustainability at the centre of urban life. It cuts carbon emissions, protects green spaces, and makes it easy to walk, cycle, or take public transport.

What is the greenest city in the world?

There is no single official ranking, so the answer depends on the method. The Green City Index from Reinders Corporation, reported by Time Out in December 2025, scores cities on green space quality, renewable energy use, air quality, public transport, bike-friendliness, and tourist taxes. It ranks Vancouver first and Oslo second. Four cities on our list appear in its top six: Vancouver, Oslo, Zurich, and Copenhagen.

What is the greenest capital in the world?

Of the capitals on our list, Oslo ranks highest in that index, in second place overall. The European Commission also named Oslo European Green Capital for 2019 and Copenhagen for 2014. Copenhagen leads our list for its cycling culture and its renewable energy goals.

How can cities become greener?

Cities can expand parks and urban forests, switch to renewable energy, improve public transport, and design buildings that use less energy.

Green Earth—making the world greener

At Green Earth, we help to make the world a greener place by planting millions of trees through our large-scale reforestation and afforestation projects. Our projects are global, with a particular focus on Africa, where we plant trees and restore forests where it is needed most. Through our projects, we restore degraded lands and ecosystems, revitalise biodiversity, and empower communities through socio-economic benefits. 

Green Earth's projects generate verified, top-tier carbon credits through the carbon emissions captured by the trees we plant. Carbon credits (also known as CO2 offset certificates) are a vital tool to restore nature as they fund these vital tree-panting initiatives and help individuals and organisations achieve carbon neutrality. By investing in our carbon credits, you invest in nature and help to create a greener world.