Despite successive efforts to improve the business banking industry many smaller firms are still getting a raw deal, according to the Bank of Scotland (BoS).

Three years have passed since a Competition Commission report revealed that UK banks were overcharging small businesses to the tune of £1 billion a year.

Since then the government and banking watchdogs have forced through minimum services that banks must offer; namely interest on in-credit accounts, free banking or both.

However, a new survey by BoS shows that many customers are still not happy with the service provided by the 'big four' - RBS/Natwest, Barclays, HSBC and Lloyds TSB - who were at the centre of the allegations.

It shows that more than a third of small firms still do not receive interest on their main business account, while a further one fifth have been made to 'apply' for the privilege.

Kevin Gillet at BoS said: "The big four incumbent banks dragged their heels for months rather than pay interest and the customers of one major bank still have to apply to get a decent rate of interest."

One positive thing to come out of the Commission's report, according to BoS, was the increased awareness among small businesses of value for money in banking. Almost two-thirds of respondents said they were 'more aware' since the report compared just 3 per cent admitting the opposite.

It is perhaps not surprising, then, that a third of respondents were actively looking for a better deal.

Since merging with the Halifax two years ago, BoS has doubled its market share in the small business banking sector. It says that from June all 700 Halifax branches will offer business banking services, while the 100 largest branches will have business banking managers on hand.

Gillet added: "With businesses increasingly focussed on value and more likely to switch bank than ever, we are happy to continue taking advantage of the big four's poor pricing."

Last year's Startups.co.uk awards put Alliance & Leicester top of the pile for small business banking.