Challenger banks also performed well, while the biggest high street banks came further down the league table.
The results form part of a new website which aims to help small firms find the best bank for their needs – and is intended to spur to banks to compete harder for clients.
The business groups commissioned ICM to survey 5,000 firms for their views on banks’ services, with sole traders making up the largest share of those questioned.
Firms can compare banks’ performance on transparency, tailored services, value, availability, and keeping customers informed.
So far the site, funded by RBS, covers 74 banking brands.
As a result some have very few reviews – for instance, one sole trader has a current account with Triodos, and gave it a 100 per cent ranking.
Looking only at those with 10 or more reviews, Nationwide topped the list with a ranking of 75 per cent
It scored most highly on fairness and clarity of its products, and slightly less well on value.
Second was the Co-op Bank, with a score of 75 per cent based on similar areas of performance.
The first entry by a big four bank was the Halifax, a part of Lloyds, with a score of 70 per cent. It scored most highly on availability and on the information given to customers.
The worst performer with more than 10 ratings was First Trust Bank, with a score of 41 per cent. It scored particularly poorly for value.