The feedback was broken down into three main categories: people, product and lending, and process.
The contrast between banks and building societies was clearest on the people category. With mutuals, responses were positive in 86 per cent of cases. However, with banks, the responses were negative in 69 per cent of cases.
While the feedback was positive for both types of lender on product and lending, mutuals again held the advantage, with 88 per cent positive responses, compared to 82 per cent for banks.
The process category inspired the most negative feedback among intermediaries. For banks, 60 per cent of the responses were negative, while with building societies around 71 per cent of feedback was positive.
Research with borrowers suggested they were similarly more content when using a building society too.
In the people category, a massive 98 per cent of responses were positive for mutuals, compared to 84 per cent for banks, while on the process category societies received 77 per cent positive feedback, slightly ahead of the 74 per cent scored by banks.
However, banks performed better among customers on products, achieving 84 per cent positive feedback, while mutuals scored 79 per cent.
The personal touch offered by building societies appears to be particularly effective, according to the report.
It states: “Building societies perform particularly well around the people-focused experience, including the skill, knowledge and overall customer service delivered by staff. Flexible lending, and the ability to cater to niche cases is also a part of the proposition that customers value.”
It’s next ‘mortgage lender benchmark’ will be published in June.
Michael Fotis, founder of Smart Money People, said: “Our analysis highlights important differences between banks and building societies which make a real impact on their customers’ satisfaction levels.
“Potential and existing customers need to know if a bank or building society will deliver the quality they demand both in terms of product and customer satisfaction.”