The FSA collected £96.7m in fines in the 12 months to the end of March, almost trebling the £33.1m taken during the previous year.
Of the total figure, £86.9m was collected through just 15 fines, according to City law firm Reynolds Porter Chamberlain (RPC).
Jonathan Davies, partner in RPC's Financial Services team, says: "The FSA has now begun the internal reorganisation that will result in its replacement and these fines show that it is making every effort to go out with a bang.
"We are now beginning to see fines for conduct that occurred at the start of the credit crunch. There has been a steady increase in the number and value of fines imposed since September 2008, but this is by far the biggest jump."
The average fine handed down by the FSA last year was up 49% on the year before, from £739,284 to £1,099,159, and they covered a range of offences from market abuse to UCIS failings.
Although the increasing revenue through fines has meant the industry has to pay less in levies, RPC is warning firms may not necessarily save money.
Davies adds: "Reduced fees are only superficially attractive for financial services firms but as these result from higher fines that are sparking massive growth in compliance costs across the City they are a pyrrhic victory.
"The reality for most regulated firms is that they are spending much more on ramping up their compliance culture than they are saving in lower fees to pay for the City watchdog."
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