Wahaca has been named the UK’s most sustainable restaurant chain by consumer group Which?

For its first ranking of sustainable practices in the hospitality sector, the watchdog said it analysed data from 22 companies, who responded to questions about how they are tackling their impact between August and November last year.

Which? assessed their answers on emissions reductions, waste and plastic, managing resources, sourcing policies, transparency and customer choice with a points-based scoring system.

The watchdog said all restaurants can do more to reduce their environmental impact.

But it found that Mexican chain Wahaca, which has 13 branches in London, Cardiff, Edinburgh and Brighton, came top with a score of 84% partly thanks to strong practices in sourcing policies, transparency and customer choices.

Frankie & Benny’s Italian-American restaurant chain was one of six awarded Which?’s Eco Provider endorsement (Alamy/PA)

Which? said the chain’s use of pork and eggs as well as reducing its beef offering and championing plant-based eating helped to boost the overall score, as did its sourcing policies for commodities such as palm oil, coffee and sugar.

It is also the only restaurant that lists carbon emissions for its meals, the consumer group added.

Off the back of the analysis, Wahaca and five other chains were awarded Which?’s Eco Provider endorsement, which indicates that companies are ahead of competitors in terms of addressing their impact.

These were Frankie & Benny’s, Nando’s, Pret a Manger, Wagamama and Young’s Pubs.

Nando’s received full marks for its waste and plastics policies after creating a low level of food waste for a business of its size, with none being sent to landfill.

Meanwhile, more than a quarter (28%) of Frankie & Benny’s menu is vegan or vegetarian, its restaurants use sustainable cleaning products and it has a sustainable policy for restaurant fit-outs, Which? said.

The consumer group said Greggs and KFC ranked the joint lowest on 38% with poor overall scoring because of not sharing data on areas such as water usage and waste.

However, Which? acknowledged that both companies have ambitious reduction targets.

The watchdog criticised Five Guys, Hungry Horse, Pizza Express, Subway, TGI Fridays and Yo! Sushi for ignoring the requests or declining to participate in the analysis.

It said restaurants must be transparent about their green policies to help consumers choose more sustainable options.

Separate research from the consumer champion found that more than four in 10 (44%) people want restaurants to be proactive about sustainability and more than a quarter (27%) would like restaurants to provide sustainability information on menus.

Shefalee Loth, a nutritionist at Which?, said: “Many people want to play their part in preventing climate change by making more sustainable choices, and they expect restaurants to support them by being transparent about their emissions and where they source their food from.

“Our research shows that some restaurant chains are doing much more than others to reduce greenhouse gas emissions and food waste.

“By visiting one of the restaurants named a Which? Eco Provider, diners can be confident they are at a chain that has impressive green credentials.”

Mark Selby, Wahaca co-founder, said: “We couldn’t have achieved this position without the tireless work being done, not just within the company but also from the incredible suppliers and producers who help to fill our menus with dishes that as well as tasting great, have a minimal impact on the environment.

“Of course, our sustainability journey is an ongoing one and we continue to explore the ways that we can, as a business, tread as lightly on the planet as possible.”

A Greggs spokesperson said: “The Greggs Pledge is our commitment to making the world a better place by 2025 focused around three key areas: building stronger, healthier communities, making the planet safer and becoming a better business.

“We continue to make good progress against our ambitious pledge targets which has not been reflected in this report as we do not yet publish all the specific data requested.”

A KFC spokesperson said: “KFC has pledged to be a net-zero business by 2040 or sooner, 10 years ahead of government targets.

“We are passionate about embedding sustainability across all areas of our business and are working with a range of experts to ensure we get this journey right.

“We believe this report does not fully reflect our position and our ongoing commitment to operating responsibly.”

A spokesperson for Hungry Horse said: “Greene King is committed to reducing its impact on the environment so that it is protected for generations to come.

“We continue to make good progress against our ambitious targets, however as we operate our ESG strategy at a wider Greene King group level, we weren’t able to provide the specific data requested for Hungry Horse.”

A spokesperson for TGI Fridays said: “TGI Fridays is fully committed to sustainability and the journey to net zero.

“Making progress on sustainability and the road to net zero will remain a key priority for us and our peers across the hospitality sector.”

A Pizza Express spokesperson said the company is “passionate” about making progress towards a target of net zero by 2040, adding: “It is disappointing to see information provided for this report was not considered for inclusion, and therefore we do not feel this report accurately assesses Pizza Express’ position or progress on sustainability.”

PA has contacted Five Guys, Subway and Yo! Sushi for comment.