To be sure, there are financial services firms moving in to London as well. In February, the financial consultancy Bovill found that around 1,000 firms from the EU, currently operating in the UK under a temporary permissions regime, are considering opening their first offices in the country.

But Wright thinks the firms that do follow through with new offices will be far fewer in number: perhaps 300-500, with much smaller volumes of assets under management when compared to the companies leaving the UK.

“As a sample, we looked at 30 banks currently using the temporary permissions regime to access the UK market, and without any physical presence as yet in the UK today,” Wright said. “With one exception, they’re all small companies. Two-thirds of them have balance sheets of less than 5 billion euros.” The really big banks and financial firms? They’re all already in London, for the most part—and they’re the ones looking towards Europe for new homes.

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