Brexit was sold to voters as a political project. The argument was about sovereignty, migration, and the right to set national laws without Brussels looking over the shoulder. What the 2016 campaign rarely mentioned, and what almost nobody spelled out in the years of negotiation that followed, was that leaving the European Union would also quietly rewire the plumbing of European finance. Nearly a decade on, the rewiring is complete. London is no longer the room where the tempo is set.
A peer-reviewed study by Amr Saber Algarhi of Sheffield Hallam University and Adeola Oyebowale of the University of Doha for Science and Technology, published in 2025, lays the shift out in numbers that are hard to argue with. The researchers tracked daily movements in the stock markets of nine European countries across two five-year windows. The first, from 2011 to 2016, covers the years when Britain was still a full member of the single market. The second, from 2020 to 2025, covers the period after the UK formally left. They applied a measure called the net volatility spillover score, which captures the difference between the turbulence a market sends to others and the turbulence it absorbs from them. A positive score means you are the one making the weather. A negative score means you are the one getting rained on.
Before Brexit, the UK scored +11.8. It was, unambiguously, the market that moved Europe. After Brexit, the UK scored -5.5. The sign flipped. London had stopped transmitting shocks to the continent and had started receiving them. Over the same interval, Germany's transmitting influence grew by nearly half, and Italy, long treated by markets as a passive recipient of stress from elsewhere, became the second most influential market in the system. Paris, Amsterdam, and Dublin picked up pieces too, but the structural change was driven by the two countries investors used to worry about rather than watch.
This is not a small methodological finding buried in an academic journal. It describes a reversal of the gravitational pull that organized European capital markets for decades.
From Pace-Setter to Price-Taker
To understand why the flip matters, it helps to remember how the old arrangement actually worked. Before 2016, if something broke in London, traders in Frankfurt, Milan, and Paris did not pause to decide whether it was relevant. They assumed it was. A downgrade of a British bank moved German bund yields. A shock to sterling pulled the euro along for the ride. Volatility on the FTSE 100 was a leading indicator, not a lagging one, because so much European capital was intermediated through London desks, London clearinghouses, and London lawyers. The passporting regime meant a firm licensed in the UK could sell into the whole EU without fresh paperwork. That made London the natural front door for the continent's money.
Passporting ended when the transition period closed on 31 December 2020. The European Commission chose not to grant the UK equivalence in most financial services, and the brief extensions that were granted, most notably for euro-denominated interest rate swap clearing through LCH, were always framed as temporary. The last of those carve-outs on euro swap clearing expired in mid-2025. Once the regulatory bridge was gone, the commercial logic that had concentrated European activity in London started to unwind on a predictable schedule.
The numbers from New Financial, a London-based think tank that has tracked post-Brexit relocations since the referendum, are by now a familiar set of figures. More than 440 financial firms have moved at least part of their operations, staff, or legal entities out of the UK into the EU. Around £900 billion in bank assets have followed, roughly a tenth of the entire UK banking system by balance sheet. No single European city has scooped the lot. Dublin leads on sheer number of relocations with about 135 firms, ahead of Paris with 102, Luxembourg with 93, Frankfurt with 62, and Amsterdam with 48. Frankfurt has taken the largest slice of actual assets, thanks to its proximity to the European Central Bank and its role in supervising euro area banking. Paris has won more of the sell-side jobs, helped by an aggressive campaign by French regulators and tax authorities to present the city as London-lite without the exit risk.
The Algarhi and Oyebowale paper argues that this redistribution did something the individual relocations did not, on their own, make obvious. It broke the network. The European financial system did not shrink, but it reorganized itself around a different center of gravity, and London found itself on the outside of the new arrangement rather than running it.
One consequence is cultural, in a way that financiers rarely admit. For a generation, if you were a continental European with ambition in markets, you went to London. The language was English. The bonuses were larger. The legal system was reliable. The concentration of talent meant a trader could move between a hedge fund, an investment bank, and a market maker inside a half-mile walk. That agglomeration is still there, and academic work by Gary Dymski and others has pointed out that sticky networks like London's do not come apart overnight. But when the regulatory link goes, the ambitious young analyst starting a career in 2025 is far more likely to be sent to Paris or Frankfurt first, because that is where the new European business is being booked.
The Stock Exchange Itself Is Shrinking
The rewiring of volatility is one story. The hollowing-out of the London Stock Exchange is another, and it has accelerated since 2023 in ways that should worry anyone who assumed the City's problems had stabilized.
In 2024, the LSE lost 88 companies, either to delisting or to relocation of primary listings elsewhere, almost always to New York. Flutter Entertainment, the gambling group behind Paddy Power and FanDuel, moved its primary listing to New York, explicitly citing deeper and more liquid capital markets. Just Eat Takeaway left London altogether, complaining about administrative burden and cost. Ashtead, the equipment rental giant, announced it was heading to the US. Tui, the travel group, took its primary listing to Frankfurt, which in 2018 would have seemed like an elaborate joke.
The trend did not slow in 2025. By the end of September, the LSE had dropped out of the top twenty global venues for new listings by capital raised, sitting in twenty-third place, behind Mexico and Oman. Fundraising from IPOs fell roughly 69 percent year on year. In the first five months of 2025, investment platform AJ Bell counted 28 cancellations on the LSE's main market and 42 on AIM, the junior market aimed at smaller firms. In June alone, three further takeovers carved out significant London names. Qualcomm agreed to pay £1.8 billion for semiconductor group Alphawave. IonQ bought quantum computing start-up Oxford Ionics for around £800 million. Private equity firm Advent bid £3.7 billion for industrial technology company Spectris.
Some of this is a global phenomenon. IPO activity has been thin everywhere since the end of the zero-interest-rate era. Some is domestic. The UK's pension system, reformed after the 2000s dot-com crash to reduce equity exposure, now holds less than four percent of its assets in UK-listed companies, down from about half in 1997. Without a large domestic buyer of last resort, British valuations have drifted lower than comparable American ones, and a lower valuation is a standing invitation to a US acquirer or to a board that wonders whether a cross-Atlantic move would fix things. The Financial Conduct Authority rewrote the listing rules in 2024 to allow dual-class share structures and give founders more control, in an open attempt to compete with New York. So far the overhaul has not changed the basic direction.
There are partisans of London who argue, with some justification, that the City's troubles are overstated. The Bank for International Settlements pointed out in a 2022 bulletin that London has held, and in some cases increased, its share of over-the-counter clearing for euro-denominated derivatives, foreign exchange trading, and international banking business measured by cross-border positions. Research by Daniela Gabriel and others has made a similar case for what they call "sticky power": London still sits at the center of a dense web of English-law contracts, global offshore jurisdictions, and time-zone advantages that Frankfurt and Paris cannot replicate. Bloomberg's own data shows financial and insurance output in the UK has grown by 2.8 percent since the 2016 referendum, which is meager but is not collapse.
This is true, and it is also beside the point the study is making. London is not ceasing to exist as a financial center. It is ceasing to set the agenda inside Europe. Those are different claims. A firm can still clear trillions in derivatives through London and find that its equity story is told in New York and its regulatory relationship is run out of Paris. That is what the numbers describe.
Why Ordinary People Notice
If all of this stayed inside trading floors, it would be a specialist story. It does not. The authors of the study make a narrow, practical point that is worth pulling out and taking seriously. When European markets are less responsive to UK signals, British firms that want to raise capital from European investors have to offer a larger discount to do so. A Manchester manufacturer issuing corporate debt into European portfolios pays more interest. A London-based FinTech pitching Series C funding in Berlin gets a worse term sheet. The price of European money, for a British borrower, has gone up.
The same thing happens in reverse on the pension side. A British pension fund that holds European equities, as nearly all of them do, now finds its returns shaped more by the mood in Frankfurt and Milan than by what is happening on its doorstep. A shock in Italian sovereign debt markets, once filtered through London traders who would translate it into sterling-denominated caution, now arrives more directly and with less warning. The member of the Universities Superannuation Scheme in Sheffield is, in a small and unromantic sense, more exposed to Italian politics than she was a decade ago and less exposed to British ones.
There is a broader effect on the cost of living that is harder to quantify but easy to describe. Mortgage pricing in the UK depends on wholesale funding markets that are themselves connected to European rates. Corporate investment decisions depend on the spreads that lenders charge, which depend on where risk is being priced. None of this shows up on a politician's slide deck, but all of it runs through the machinery that sets the price of a fixed-rate mortgage in Liverpool or the interest on a small business overdraft in Cardiff.
A personal example makes the shift easier to feel. Before 2016, if you worked on a European credit desk, the morning meeting in London set the tone for the day. Paris and Frankfurt called in with local color, but the book was run from Canary Wharf. Ask someone on an equivalent desk today where the book is run, and the answer is almost always Paris or Frankfurt, with a London presence that handles sterling products and a handful of cross-border relationships. The London desk is still there. It no longer runs the show.
A Permanent Reorganisation
It is tempting to treat all of this as a cyclical story, the kind of dip that could reverse if a future UK government negotiated equivalence, or if the EU got tired of running its own clearing, or if a generous US administration pushed Europe back toward London for strategic reasons. The authors of the 2025 study are skeptical, and their skepticism rests on a structural argument rather than a political one. The overall connectivity across European markets, the total volume of cross-border signal, did not fall after Brexit. It just routed around London. Networks that have rerouted once do not tend to reroute back, because each additional year of operation adds infrastructure, relationships, and legal habit that would have to be rebuilt from scratch to reverse the change.
The UK-EU summit held earlier in 2025 produced some warm words on trade in goods and on defense cooperation. It produced almost nothing on financial services. The Starmer government, for all the political distance it has tried to put between itself and the 2016 settlement, has not attempted a major renegotiation of the financial services relationship, and there is no political constituency in the EU pushing for one. Brussels has spent five years building up its own supervisory capacity, its own clearing, and its own listing infrastructure. A Belgian or Dutch official asked to dismantle that to let London back in has no reason to say yes.
Inside the City, the conversation has shifted accordingly. The talk is no longer about winning back European business. It is about specialization. Green finance. Digital assets. FinTech, where London still raises more funding than Paris and Frankfurt combined. A more permissive domestic regulator. A lighter listing regime. All of that may work. None of it depends on Europe paying attention.
An executive at a mid-sized British asset manager put the change to me in a single sentence a few months ago. Before Brexit, she said, the European job was run from London with some people on the continent. Now the European job is run from the continent with some people in London. It is the same business, more or less the same profit and loss, and the same names on the doors. Only the direction of the flow has changed.
That is the shift the spillover numbers are measuring. Britain is not a smaller financial center than it was in 2016. It is a financial center that has stopped running Europe and has started reacting to it. For a country that spent a generation selling the world the idea that the City of London was the engine room of European capitalism, that is a big thing to have misplaced in a decade.