The figure of 2.26 million transactions given by CLS head David Puth underlines the stakes in a record day's trading that led to the collapse of a handful of brokerages and investment funds, and tens of millions of dollars of losses at major global banks.

Puth said overall global trading volumes after the Swiss National Bank's move last Thursday reached $9.2 trillion, almost doubling the average turnover in what is already the world's biggest financial market by volume.

That was also the second biggest day ever on currency markets by volume of trade, topped only by the $10.67 trillion recorded on Dec. 17, when Russia's rouble was collapsing along with crude oil prices.

CLS is used almost universally by the banking industry to process or settle trades and hence provides the best running count of the scale of foreign exchange trading, up to 90 percent of which is now done electronically.

Financial sector managers are still picking up the pieces of the chaotic few minutes in which the franc surged by as much as 40 percent, by far the biggest moves in a major currency since the world moved to floating exchange rates in the early 1970s.

Barclays lost tens of millions of dollars from the moves, an industry source told Reuters last week, and dealers say there may have been heftier losses for others among the handful of banks who control more than 60 percent of trade in a market that runs all day every day.

Online retail trading platform Alpari went into administration on Monday and U.S.-based rival FXCM had to seal a $300 million loan to prop itself up last Friday.

Bankers say there may be more high-profile casualties to come from the fund management industry, where losses on bets that the franc would weaken come after a year of minimal or negative returns for many.

(Reporting by Patrick Graham; editing by John Geddie/Ruth Pitchford)

By Patrick Graham