The Great Financial Flit: 5 Reasons London is Feeling a Bit Thin

Let’s be honest: we were told there’d be sunlit uplands. Instead, it looks like we’ve handed the keys to the kingdom to Dublin and Paris while we sit here wondering where all the £1.3 trillion went.

The latest data on the post-Brexit financial migration is out, and it’s a proper "slow-burn" shambles. While the UK is busy "sovereignty-ing" itself into a corner, our neighbours across the Irish Sea are having a literal field day.

Here are my 5 biggest takeaways from the economic fallout that’s currently hollowing out the City (London).

1. The £1.3 Trillion Vanishing Act

Remember when people said the City of London was "too big to fail"? Well, it turns out it was just big enough to leak. Banks and insurers have moved over £1.3 trillion in assets to the EU. That’s roughly 10% of the entire UK banking system just... gone. It’s not just paperwork; it’s the capital base for future investment, and it’s now sitting in vaults where "passporting" isn't a dirty word.

2. Dublin: The New English-Speaking King

If London was the old king, Dublin is the young, tech-savvy heir that actually gets along with its neighbours. Capturing 25% to 30% of all Brexit-related moves, Dublin has welcomed 135 firms with open arms. JPMorgan, BofA, and Citi aren’t just "opening offices"- they are shifting balance sheets worth over £90 billion.

3. The "Slow-Burn" GDP Slump

This isn't an overnight crash; it’s worse. It’s a stagnation. UK GDP per capita is estimated to be 6% to 8% lower by 2025 than it would have been if we’d stayed put. Business investment has taken a 12% to 18% hit because firms were too busy doing "contingency planning" (translation: figuring out how to leave) instead of actually growing.

4. The Office Space Paradox

Dublin’s office vacancy is sitting at 18.6%, which sounds rubbish until you look closer. There is a "flight to quality." While general space is empty because of hybrid work, the "Grade A+" sustainable buildings are being snapped up by international firms faster than you can say "Silicon Docks." London, meanwhile, is seeing prime rents rise simply because we aren't building enough, even as we lose the tenants.

5. The Great Services "Switch"

This is the one that really takes the biscuit. Since the referendum, Ireland’s services exports have boomed by £126 billion (a 24% rise). At the exact same time, UK services exports fell by £113 billion from their previous trend. It’s not a mystery - it’s a direct switch. We’re literally exporting our competitive advantage across the Irish Sea.

The numbers

Table 1: Estimated Long-Term Macro-Economic Impact on the United Kingdom (2025)

The Office for Budget Responsibility (OBR) maintains that the Trade and Cooperation Agreement (TCA) will reduce long-run productivity by 4% compared to EU membership, with both exports and imports projected to be 15% lower in the long run.⁹ While the UK current account deficit reached record highs of 7.7% of GDP in early 2022, driven partly by energy prices, the underlying deterioration of the goods and services balance reflects the loss of competitive advantage in the European market.¹⁰

Table 2: Financial Sector Company Relocations by City (2021 Analysis)

The sectoral composition of moves to Dublin is particularly dense in asset management and insurance. Over 40% of all asset management firms that relocated or established new EU hubs chose Dublin, leveraging Ireland's pre-existing status as a global hub for fund administration.¹¹ Large-scale commitments from global institutions underscored this trend. JPMorgan purchased an office in Dublin's Docklands for 1,000 staff, while Bank of America designated Dublin as its primary EU hub, incurring costs of approximately $400 million to prepare for the transition.³ Similarly, Citi expanded its Dublin-based balance sheet to over $90 billion in 2021, an increase of 22%, with plans for significant further growth.³

Table 3: Identified Asset and Personnel Transfers from the UK (2021-2022)

The "substance" requirement imposed by EU regulators, including the European Central Bank (ECB) and the Central Bank of Ireland, has ensured that these relocations are not merely "letterbox" operations.¹ Regulators have increasingly required firms to maintain sufficient local staff and senior management in their new EU hubs to justify their licenses and ensure effective risk oversight.¹¹ This has led to a "second wave" of relocations, as firms move more senior personnel and front-office functions to satisfy these mandates.¹⁵

Table 4: Ireland's General Government Tax Revenue (2019-2024) in €Millions

*Note: 2024 Corporation Tax figure excludes €10.95 billion one-off Apple State-aid ruling receipt.²⁰

The concentration of this revenue is a point of both strength and vulnerability. Foreign-owned multinationals paid €24.8 billion in corporation tax in 2024, accounting for 88% of the net total.²⁰ Furthermore, the top ten corporate groups in Ireland account for 57% of all net corporation tax receipts.²⁰ While much of this is driven by the pharmaceutical and ICT sectors, the financial services sector contributes significantly through both corporate profits and the high income tax yields from its workforce.²¹ The relocation of high-earning financial professionals generates a substantial "salary uplift," with international financial roles in Dublin often commanding salaries significantly above the national average, leading to an incremental tax gain per job of over €11,000.²³

The Personal Favourite: The "Substance" Rule

My personal favourite bit of this whole mess? The "substance" requirement. EU regulators aren't stupid; they’ve banned "letterbox" operations. If you want a license, you need real people, real desks, and real senior managers in the EU. This has triggered a "second wave" of relocations that is stripping the City of its highest-value personnel.

The Reality Check: Once these firms have spent hundreds of millions setting up hubs in Dublin or Paris, they aren't coming back. These are "sunk costs" that have permanently shifted the centre of gravity.