For more than two decades, international financial centres have been subjected to a steady succession of global tax initiatives, usually accompanied by predictions of substantial revenue losses arising from tax avoidance, profit shifting and, sometimes less carefully, tax evasion.
A new Organisation for Economic Co-operation and Development (OECD) working paper released on 15 July 2026 provides an interesting opportunity to examine some of those assumptions against actual results.
The paper, MNE Responses to the Global Minimum Tax, is particularly useful because, unlike much of the analysis preceding the introduction of the Global Minimum Tax, it examines what actually happened after implementation began in 2024.
The revenues are lower than forecast
The OECD estimates that the Global Minimum Tax increased global corporate tax revenues by between €79 billion and €109bn in its first year, equivalent to approximately 2.4% to 3.4% of global corporate income tax revenues.
That is not insignificant. But it is considerably below what had previously been forecast.
The paper notes that earlier OECD estimates anticipated first-year revenues of US$155bn to US$192bn. The latest empirical assessment puts the corresponding figure at approximately US$86bn to US$118bn.
The amount of additional taxable revenue available to be captured appears, at least so far, to be smaller than anticipated.
An already transparent system
There is a wider context that should not be ignored.
Jurisdictions such as the Cayman Islands had already spent many years (and millions in implementation costs across the industry) implementing extensive tax transparency and information-sharing arrangements before the Global Minimum Tax arrived. Cayman implemented the US Foreign Account Tax Compliance Act (FATCA), became an early adopter of the Common Reporting Standard (CRS) and began CRS exchanges in 2017.
This matters because the popular international narrative has sometimes continued to portray offshore centres as places where taxable assets or income can simply ‘disappear’ from the view of overseas tax authorities.
That description has become increasingly difficult to reconcile with the architecture actually in place.
None of this means that tax evasion does not occur internationally, or that multinational businesses do not engage in tax planning. The OECD paper itself finds a greater tax impact among multinational groups more likely to have engaged in tax planning. But legal tax planning, aggressive tax avoidance and criminal tax evasion are different things and public debate has not always been sufficiently disciplined in distinguishing between them.
Regulation or competition?
This leads to a more uncomfortable question.
If increasingly sophisticated information-sharing systems already allow tax authorities to identify their taxpayers and obtain financial information, and subsequent global tax initiatives produce less additional revenue than initially forecast, we should at least consider whether every additional layer of international regulation can be justified entirely by the risks normally cited in support of it.
There has always been another dimension to the offshore debate: competition for legitimate international capital.
International financial centres facilitate cross-border investment precisely because they provide tax-neutral platforms through which investors from different jurisdictions can pool capital without introducing an additional layer of taxation at the vehicle level. Investors remain responsible for taxation in their home jurisdictions.
Ironically, many of the ultimate beneficiaries of that efficiency are businesses and investors located within OECD economies themselves. Cayman structures are extensively used to facilitate investment into companies, infrastructure and other assets in those same economies.
There is therefore nothing wrong with continuing to improve international tax cooperation where genuine weaknesses are identified. Cayman has repeatedly demonstrated its willingness to do so.
But regulation should remain proportionate to identifiable risks. We should be equally willing to examine the evidence when it suggests that the problem being addressed may not be as large as originally assumed.
The OECD’s latest findings do not settle that debate. They do, however, provide another reason to have it.
