UK Banks Getting Volatility-Ready Before EU Referendum Results

— -- The biggest banks in Britain, including many U.S. banks with London operations, are preparing for an all-nighter as U.K. residents vote today on whether to remain in the European Union.

Official results of the referendum are not expected before 1 a.m. ET Friday, though first indications are expected around 6:30 p.m. today. Either way, bankers and traders are preparing for volatility on financial markets.

“Whatever the result, it’s going to be a sleepless night for our traders as the results come in slowly on Friday morning,” Joe Rundle, head of trading at ETX Capital, a U.K.-based financial company, said in a statement.

“There could be some potentially wild gyrations in prices, particularly in sterling. Some banks are warning that they might fail to execute orders on their electronic trading platforms.”

Goldman Sachs, JP Morgan Chase, Barclays, and Citibank are among those bringing in extra staff to man a 24-hour trading desk and help clients manage their risks.

"At present the pound is on the up as investors bet on a remain [in the European Union] win," Rundle said, adding, "at the same time the cost of insuring against massive moves in sterling has skyrocketed."

The pound has already surged, reaching a level it had not seen since the financial crisis of 2008, according to the financial markets expert.

“It’s an incredible opportunity for traders to make big bets on the fortunes of the pound and other markets affected by the referendum such as the FTSE,” Rundle added.

The European Central Bank’s chief said they are preparing for "all possible contingencies" in the event of a vote for the U.K. to leave the European Union.

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