Sustainable bank Triodos has been named the best financial institution for environmentally conscious savers, according to a new report from Which?.

Although building societies crowded the top of the company鈥檚 index, Bristol-based Triodos topped the ratings. Joint second were Nationwide and Ecology Building Society.

Which? ranked 18 banks and building societies based on publicly available information. They were rated across four categories: environmental reporting, carbon management and reporting 鈥 the most important category 鈥 transparency and ethos.

The Co-operative Bank finished sixth, while NatWest, Lloyds, HSBC and Barclays languished in mid-table.

The Co-op did well because of a target not to send waste to landfills, but its sustainability report did not elaborate on how it helps customers deal with their environmental impact.

Meanwhile, Santander was named the worst-performing high street bank on the index.

Which? said more than a quarter of its members cared about the values of the companies they invest their savings in. But more than two-thirds said they would not know how to find information about a bank鈥檚 green credentials.

Jenny Ross, Which? Money editor, said providers needed to be "more transparent" to help consumers compare and make informed choices.

鈥淚t can be incredibly difficult for consumers to gauge how sustainable a product or company is, but when it comes to savings providers our research shows building societies and specialist banks are doing a better job on sustainability and transparency, compared to high street banks,鈥 she said.

鈥淲hile interest rates are often the deciding factor when choosing a savings provider, we know some consumers would consider moving their money if they found it was invested in industries that harmed the environment.

Earlier this month, Triodos topped a global league table for funding the most clean energy deals in the world last year.

The institution, which is based on Deanery Road, financed more than $433m (拢310.9m) green deals in 2020.

Triodos Bank chief executive Bevis Watts said: 鈥淪ustainability is absolutely at the heart of Triodos Bank and we鈥檙e pleased to enable people鈥檚 money to be used as a force for good through our savings accounts, as well as current accounts and investments.鈥

A spokesperson for Santander said: 鈥淥ur purpose is to help people and business prosper, which permeates the way we conduct our business and it is at the core of our sustainability strategy.

鈥淲e are committed to recognising the impact we have on all our stakeholders, and aim to be responsible in everything we do.

鈥淲e have invested in developing a 海角视频-wide sustainability strategy and over the last year we evolved our priorities and ambition levels to ensure we accelerate our journey to become a truly responsible bank.鈥

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