The UK spider's web: how Britain runs the world's largest tax-haven network

The single most important fact about offshore finance is also the least advertised: the largest tax-haven network on earth is British. Three of the four worst corporate tax havens in the world are British territories. At the centre sits the City of London; around it, in two rings, sit the Crown Dependencies and the Overseas Territories, channelling money inward. The United Kingdom has the legal power to change any of it, and has chosen, repeatedly, not to. This is the signature page of this site, because it is the story the UK is most comfortable leaving untold.

The phrase "spider's web" is not ours and it is not rhetorical. It was coined by an investigative journalist in a 2011 book on offshore finance and has since been adopted by the Tax Justice Network as its standard description of Britain's offshore architecture. The image is structural, not decorative. The City of London is the body of the spider. Radiating out from it are two rings of satellite jurisdictions that pull money in toward the centre, where the banks, exchanges and law firms that service it are clustered.

The arithmetic of the web

Add the United Kingdom together with its Crown Dependencies and Overseas Territories and treat the whole thing as one entity. On the Tax Justice Network's October 2024 figures, that entity is responsible for about a third of the entire world's corporate-tax-abuse risk, costing other countries on the order of USD 84 billion a year in lost corporate tax. Counting private wealth as well as corporate profit, the figure the network puts on the British network's damage rises to around USD 169 billion a year.

There is a second way to measure the same network, and it is worth keeping the two apart. The Tax Justice Network's State of Tax Justice dataset measures how much tax loss each jurisdiction inflicts on other countries. On that cut, the UK and its network together account for about 26% of the corporate tax revenue lost by all countries, around USD 129 billion a year. Different method, same conclusion: no other power comes close to the scale of what Britain enables.

The web does not work by Britain having no rules. It works by Britain keeping respectable-looking rules at home while its satellites keep the permissive ones, with a constitutional distance between the two that lets the UK present the territories' tax policy as a matter for them. The Tax Justice Network calls this posture "hypocritical," and the constitutional facts below are why.

The centre: the City of London

The City of London is a square mile inside Greater London with its own ancient corporation and its own peculiar governance, much of it predating the modern British state. What matters here is its function, not its folklore. The City is where the global banks, clearing houses, commodity and insurance markets, including Lloyd's, and the law firms cluster. It is the infrastructure that processes, prices and legitimises the money arriving through the satellite jurisdictions, and it lobbies hard to preserve the conditions in those satellites that feed it.

The inner ring: the Crown Dependencies

Three jurisdictions form the inner ring. They are not part of the United Kingdom and they are not, and never were, members of the European Union, but they owe allegiance to the Crown and depend on the UK for defence and foreign affairs. Each has a specialism:

• Jersey: private banking, trust structures and fund administration. No capital gains tax, no inheritance tax.
• Guernsey: captive insurance, private equity and investment funds.
• Isle of Man: insurance, e-gaming and aircraft registration and leasing.

All three score the maximum 100 out of 100 on the Corporate Tax Haven Index's haven measure. Their individual shares of the global total are smaller than the big Overseas Territories only because their scale is smaller, not because their rules are tighter.

The outer ring: the Overseas Territories

Seven of the fourteen British Overseas Territories operate as significant offshore financial centres. The three that dominate are the reason this network tops the table:

(The Crown Dependencies sit in the same index: Jersey 4.1%, Isle of Man 2.7%, Guernsey 2.6% of global corporate-tax-abuse risk.)

The British Virgin Islands is the single largest node in the network, at 7.1% of the global total. Its role is rarely to be the final resting place of money; it is the share-holding layer in the middle of a complex structure, a company that owns other companies, offering confidentiality without any real operations. Its corporate vehicle has no corporate tax, no withholding tax, and historically no public register of who owns it. (The vehicle is now formally the "BVI Business Company" under the 2004 Act, which replaced the older International Business Company; the brass-plate function is unchanged.)

The Cayman Islands, at 6.7%, is the world's dominant centre for investment funds: around 12,700 mutual funds are registered there, and a majority of the world's hedge-fund assets are domiciled in Cayman by one measure or another. It levies no direct taxes of any kind: no corporate income tax, no capital gains tax, no withholding tax, no payroll tax.

Bermuda, at 5.8%, is chiefly a reinsurance centre and a home for holding companies seeking full tax exemption.

A fourth territory deserves a line for what changed rather than what it is. Gibraltar was, before Brexit, the only British Overseas Territory inside the European single market, which made it valuable for EU-facing online gambling and financial products. That access ended with Brexit, and with it Gibraltar's particular niche.

Who answers for it

Here is the part the UK's official position works hardest to avoid. The government's line is that the Crown Dependencies and Overseas Territories are self-governing, and that their tax policy is a matter for them. As a matter of constitutional law, that is not the whole truth. The UK Parliament holds the power to legislate for the Overseas Territories and to override the Crown Dependencies, and the Crown appoints the senior officials, the Governors, in the Overseas Territories. The distance is political, not legal. Westminster could change any of this. It has the votes and it has the authority.

What it has done instead is move slowly and incompletely. The 2022 Economic Crime (Transparency and Enforcement) Act is often described as having forced the territories to open public registers of who really owns the companies registered there. That overstates it. The territories committed to registers, then downgraded the commitment from fully public access to access only for those who can show a "legitimate interest," and most have missed their deadlines. As of 2025, the Cayman Islands had launched a legitimate-interest register; the British Virgin Islands had slipped implementation toward 2026. The promise was transparency. The delivery, so far, is mostly delay.

A word on secrecy, dated honestly

For years the Tax Justice Network observed that if you aggregated the British network with the UK itself, the combined entity would top the Financial Secrecy Index above Switzerland. That was true of the older editions of that index, around 2018. It needs a date now, because in the current Financial Secrecy Index, the 2025 edition released in June 2025, the jurisdiction ranked first in the world for financial secrecy is the United States, with Switzerland second. The British network remains enormous; it is simply no longer the single secrecy story it once was, and we will not pretend the 2018 framing is current.