Europe’s largest hostel chain, a&o Hostels, has released its 2025 Sustainability Report, detailing a 1.9% reduction in CO2e emissions per overnight stay to 3.58 kilograms. The improvement comes as the group expanded its portfolio to 46 properties, with four new openings that pushed total emissions up 3.1%.
ESG Director Arben Maliqi presented the report, which underscores a&o’s strategy of curbing direct emissions through energy efficiency, renewable energy procurement, and waste reduction. CEO Oliver Winter said: “The travel industry is constantly evolving, and a&o is actively shaping this transformation by combining growth with our commitment to further reducing energy consumption and using resources responsibly.”
Conversion-First Growth Model
Of a&o’s 46 locations, 43 are conversions of existing buildings — a model that inherently reduces the carbon footprint of expansion. The chain is collaborating with the Technical University of Berlin on a life cycle assessment for its new Berlin hostel, which is intended to serve as a blueprint for future projects. Key operational initiatives include sourcing 100% green electricity, digitizing guest registration to cut paper use, and supporting cultural heritage projects.
In 2025, a&o hosted nearly three million guests, generating 6.6 million overnight stays. The three locations with the lowest emissions per stay are in Copenhagen and Berlin, reflecting the group’s focus on energy-efficient design in urban markets.
The chain invested €378,000 in employee training and continues to back social and cultural programs. It also received the “A World for Travel Societal Development Award” and earned a strong ESG profile rating from Sustainable Fitch. Since 2015, a&o has cut CO2e emissions by 76%.
For travel professionals, a&o’s results offer a case study in balancing growth with sustainability — a challenge that resonates across airlines and hotels eyeing expansion in a carbon-constrained world. The full report is available on a&o’s website.
