How Much of UK Gambling Really Happens Offshore?

Ask five different sources how large the UK’s offshore gambling market is, and you’ll get five different numbers. The Campaign for Fairer Gambling says 9% of the online market, citing Yield Sec data. The Betting and Gaming Council says 1.5 million Britons staking 4.3 billion pounds. H2 Gambling Capital projects offshore activity growing 110% after the tax increase. The UKGC tracks more than 1,000 illegal operators but doesn’t publish its own market share estimate. And Nordic academic researchers argue that many of these figures are inflated for political purposes.

After years of working with all of these sources, I can tell you that the honest answer to “how much gambling happens offshore” is: we don’t know precisely, everyone who claims to has an agenda, and the truth is important enough to be worth examining carefully rather than accepting any single estimate at face value.

Who Produces Offshore Estimates and How

Understanding the number starts with understanding who produced it and why.

The Campaign for Fairer Gambling commissioned Yield Sec – a gambling compliance technology firm – to monitor unlicensed gambling activity targeting UK consumers. Their methodology involves tracking website traffic, advertising networks, and payment flows associated with identified illegal operators. The resulting estimate: illegal operators control approximately 9% of the UK online market, extracting 379 million pounds in the first half of 2025. The Campaign for Fairer Gambling advocates for stricter regulation and enforcement, meaning a larger offshore estimate supports its policy position. That doesn’t make the number wrong, but it does mean the methodology and assumptions deserve scrutiny.

The Betting and Gaming Council represents licensed operators. Its estimate of 1.5 million Britons staking up to 4.3 billion pounds annually on the unregulated market comes from a combination of industry data, consumer surveys, and traffic analysis. The BGC has a clear incentive to present the offshore market as large and threatening: it argues that tax increases and regulatory tightening push consumers toward an unregulated market where no tax is collected and no protections apply. A larger offshore estimate strengthens the case for lower taxes and lighter regulation on licensed operators.

H2 Gambling Capital is an independent research firm that produces market forecasts for institutional clients. Its projection that onshore iGaming channelisation will fall from 92-93% to approximately 80% after the tax increase is modelling-based, drawing on historical data from other markets that have experienced similar tax shocks. H2GC’s commercial model depends on the accuracy of its forecasts rather than on any specific policy outcome, which gives its estimates a degree of independence that advocacy organisations don’t share – though forecasts are inherently uncertain and depend on assumptions about consumer and operator behaviour.

The Nordic Critique – Estimates as Political Tools

The most systematic critique of offshore gambling estimates comes from Nordic academic researchers, including Virve Marionneau at the University of Helsinki and Soren Kristiansen at Aalborg University. Their work examines how offshore gambling data is produced, cited, and deployed across European policy debates.

Their central argument: offshore estimates are likely to be political tools. Industry groups inflate offshore figures to argue against regulation and taxation. Regulators sometimes understate them to avoid appearing ineffective. The actual measurement methodologies are rarely subjected to independent peer review, and the assumptions embedded in each estimate – how “offshore” is defined, what data sources are used, how traffic and revenue are modelled – vary significantly between producers.

This critique resonates with my own experience. I’ve seen the same data point cited by both sides of a policy debate with entirely different framing. The BGC cites offshore growth as evidence that taxes are too high. The Campaign for Fairer Gambling cites the same growth as evidence that enforcement is underfunded. Neither cites the data that would undermine their preferred narrative. This isn’t unusual in policy debates, but it means anyone trying to understand the actual size of the offshore market needs to triangulate between sources rather than accepting any single one.

The Nordic researchers don’t argue that offshore gambling is negligible – they acknowledge it’s real and significant. Their argument is that precise-sounding figures (9%, 4.3 billion, 110% growth) create false confidence in estimates that carry wide uncertainty margins. A range – say, 5-15% of the UK online market – would be more intellectually honest than a single-point estimate, even if it’s less useful for newspaper headlines and policy advocacy.

Finding Signal in Noisy Data

So what can we actually conclude? More than you might think, if you focus on the areas where different sources converge rather than where they diverge.

All sources agree that the offshore market is growing. Whether it’s 7% or 12% of the UK online market, the direction is consistently upward. No credible analysis published in the past two years projects the offshore market shrinking under current or announced policy conditions.

All sources agree that the April 2026 tax increase will accelerate offshore migration. The magnitude is debated, but the direction is unanimous. A 40% duty on gross gaming yield fundamentally changes the economics of the licensed market, and some portion of the value gap between licensed and unlicensed play will be absorbed by consumers moving offshore.

All sources agree that enforcement has measurable impact but doesn’t eliminate the offshore market. The UKGC’s own data – 327,964 URLs flagged, 203,571 removed, 592 cease-and-desist orders – demonstrates real activity. But the persistence of more than 1,000 tracked operators suggests that enforcement disrupts without eradicating.

And all sources agree, at least implicitly, that measurement itself is part of the problem. The offshore market is, by definition, operating outside regulatory visibility. Any estimate requires inference from indirect indicators – web traffic, payment flows, consumer surveys – rather than direct observation. The uncertainty is structural, not fixable by better methodology alone.

What I recommend, as someone who works with these numbers professionally: treat every offshore estimate as directional rather than precise. The offshore market is real, it’s growing, and the tax increase will make it grow faster. The exact numbers matter less than the trajectory – and every stakeholder in this debate has an interest in the trajectory they project. Read the number, then read who produced it and why. The context is more informative than the figure. For the specific projections driving the current policy debate, I’ve examined H2 Gambling Capital’s modelling and the government’s own forecasts in the analysis of the 40% Remote Gaming Duty.