Senior banking figures are frustrated by the swaps payouts, believing that the authorities have changed the rules in retrospect.
The City watchdog found that 90% of interest rate swaps sold to small businesses were mis-sold, and customers are entitled to compensation.
An FSA review found that more than 90% of so-called interest rate swaps sold to businesses were mis-sold. But what are they?
Among those critical of the length of time banks have taken to pay compensation to those wrongly sold insurance products is campaign group 'Bully Banks'
In a letter to Vince Cable, Bill Haslam, of Bully Banks, said: "2,800 people have been employed by the banks to deal with (after the sophistication tests) 15,000 cases, I am only a non-sophisticated small businessman of course but this is five cases per person?
"Many of these people are on £900 a day, as these jobs have been heavily advertised, and presuming an average daily cost across the 2,800 recruited of £300 per day per person this is a staggering £840,000 per day.
"If we said that they had all been working on this for only three months (when we know in truth many have been on this for a year now) this would be a staggering £76 Million.
"And yet the FCA and all these clever people at the banks have only managed to payout a grand total of £500,000 in 14 months to ten firms that were mis-sold!"
The Federation of Small Businesses has said it is "quickly losing confidence" in the banks and the regulator over the mis-selling of complex financial products.
– John Allan, National Chairman, Federation of Small Businesses
...the FCA [Financial Conduct Authority] has laid bare depressing figures which show that after five months only ten businesses out of over 15,000 currently in the process have been offered compensation.
What makes this even more disappointing is that 1,300 firms who should be offered redress straight away are still stranded in this inept compensation scheme.
We are quickly losing confidence in the banks and the regulator as this scheme remains unbelievably slow.
Britain's markets watchdog said banks have started paying compensation for mis-selling of interest rate swaps and the bill is expected to increase rapidly over coming months.
The products were designed to protect smaller companies against rising interest rates but when rates fell, they had to pay large bills, typically running to tens of thousands of pounds. Companies also faced penalties to get out of the deals, which many said they had not been told about.
The Financial Conduct Authority said in a statement on Wednesday that by the end of August 10 offers of redress had been accepted by businesses totalling £500,000.
The FCA says it expects rate swaps compensation offers to increase rapidly in coming months with 210 offers already sent to customers, with 1,700 due shortly.
The UK Financial Conduct Authority says 10 offers of redress for interest rate swaps mis-selling were accepted by the end August, totalling £500,000.
UK banks were hit with a hefty compensation bill after a review of complex products sold to small businesses found more than 90% had been mis-sold.
Business Secretary Vince Cable said it was "unbelievable" that some bankers still expected bonuses.
ITN News Business Editor Laura Kuenssberg reports.
The Business Secretary Vince Cable told ITV News it was "unbelievable" some bankers still wanted big bonuses. He said after everything that had gone wrong the public would not understand.
Greg Clarke, Financial Secretary to the Treasury, said banks must work with independent assessors and their customers to determine the amount of compensation due to clients who were mis-sold interest rate swaps:
The British Bankers Association has welcomed today's report from City watchdog, the Financial Services Authority, into mis-sold interest rate swaps, and has said their members will work with customers affected by the scandal, "prioritising those with the greatest need."
The announcement today will give clarity to businesses and will enable the banks to put in place the steps needed to resolve each case for customers. Where customers have suffered unfairly the banks have all agreed that they will put it right.
– BBA Chief Executive, Anthony Browne.
Banks will be contacting those companies affected shortly, prioritising those with the greatest need. Any business which is currently facing financial distress and is seeking a suspension of payments should get in touch with their bank immediately.