How Big Is the Gambling Black Market? A Global View of the Estimates

By iGaming Review · Published 15 October 2026

From a US$293 billion global online market estimate to national figures measured in millions and billions, the scale is substantial. We examine thirteen markets, compare the shares outside domestic licensing systems and explain where the evidence differs.

The Netherlands’ regulator data imply approximately €1 billion in illegal online gambling revenue in 2025. A US industry study puts illegal online slots and table games at US$18.6 billion over a twelve-month period. An Australian study estimates A$3.9 billion offshore in 2024.

These are substantial sums, but they describe different markets. To widen the perspective, we begin with a global model, then examine twelve countries through one common framework before looking at the amounts and evidence behind individual estimates.

The Global Estimate

H2 Gambling Capital’s April 2026 update estimates worldwide online gross gaming revenue at US$293 billion in 2024, with approximately 55 percent offshore. Its model supplies a global scale; national studies show how uncertain the composition can be.

How much of the world do the case studies cover? Their combined share cannot be calculated reliably from these sources: the available country amounts use different years, products and models. The examples below span Europe, North America and Oceania; they are a selection of evidence, not a representative global sample. Major parts of Asia, Latin America and Africa remain outside this country comparison.

Twelve Markets, One Modelling Framework

Using one provider and year gives a broader, more consistent starting point. This comparison shows H2’s estimated 2024 online betting and gaming revenue split. Lotteries are excluded. Each country’s bar totals 100 percent; a percentage is not that country’s share of worldwide revenue.

Putting the Amounts in Proportion

The following six comparisons pair amounts with a defined market total. Two historical estimates follow. Each bar represents 100 percent of the market specified on that card. All amounts use revenue after winnings, rather than total stakes. Years and definitions differ, so these cards should not be read as a ranking or as a continuation of the H2 series above.

The United Kingdom illustrates the distinction between a commercial estimate and an official one. H2’s May 2026 release gives £685 million in offshore online betting and gaming gross yield for 2025. Its separate £16.6 billion headline measures stakes. The Gambling Commission’s November 2025 assessment said it was not ready to publish a credible overall market-size estimate for Great Britain. A commercial figure should not be presented as the regulator’s finding.

Why the Share of Players Tells a Different Story

The monetary estimates make the Dutch player figures especially revealing. For the second half of 2025, the Ksa estimated that 91 percent of online players used only legal providers, while the licensed share of GGR was 53 percent. That implies an illegal revenue share of about 47 percent for July–December, compared with our approximately 46 percent calculation for the full year. The regulator’s release presents the two measures together. A relatively small share of players can account for a much larger share of money.

Method

Two measures · same period

Keep in mind

91% counts players; 53% measures revenue. These are not competing estimates of the same share.

One Market, Several Measurements

Channelisation describes how much activity remains within a country’s licensed gambling system. The word can make unlike measurements sound interchangeable. A person, a player account, a website visit and a euro of gambling revenue are different units.

Mixed use adds another decision. The Ksa’s full report gives a player-based estimate of 95 percent when people using both legal and illegal providers are included on the legal side, compared with 91 percent for exclusively legal use. These are half-year averages of monthly measures; the report covers gambling under the Dutch remote-licensing system and excludes lotteries. The definition changes the answer without changing anyone’s behaviour. [Ksa, section 3.1]

Where the Estimates Come From

The Dutch player and revenue estimates also come from different systems. In a June 2026 parliamentary response, the government described the player measure as drawing on GfK’s monitored panel of roughly 6,000 people, including about 300 online players. Monitoring software records behaviour on participants’ computers and mobile devices. The response explicitly cautioned against extrapolating from the small player sample. [Dutch government, 1 June 2026]

For the illegal market’s revenue, the Ksa uses a model linking searches for gambling brands to revenue information. Its methodology document describes Google Ads search volumes for brand-specific terms, not a record of bets or payments. The model is calibrated against available operator revenue data, with limited observations for illegal providers and assumptions about the relationship between searches and revenue.

These are useful attempts to observe a market that does not provide comprehensive regulatory returns. But placing the resulting percentages next to one another does not turn them into matched records of individual players and their losses. Dividing the estimated illegal revenue share by the share of people classified as using illegal providers during the period would not produce a reliable figure for the average illegal-market customer.

Great Britain’s Gambling Commission identifies a similar problem in its assessment of a traffic-based channelisation method. Turning engagement into revenue requires assumptions about spending behaviour in the legal and illegal markets. Apps also need to be accounted for. Uncertainty in both sides of the comparison carries through into the resulting ratio.

Surveys pose different challenges. The Commission’s methodology review explains why it did not pursue expenditure surveys for its own market-size estimate: recalling gambling expenditure is difficult, and respondents may not know whether the sites they use are regulated. That is a reason to inspect a survey’s questions and limitations, rather than treat every survey result as measuring the same thing.

The Revision That Changes the Story

Even figures from the same regulator require care when compared over time.

The Ksa’s autumn 2025 report put revenue-based channelisation at 49 percent for the first half of 2025. Reading that alongside the spring report’s 53 percent could suggest an improvement.

The full spring report tells a different story. The regulator removed anomalous search volumes associated with three providers, which it suspected had been artificially manipulated. Its revised series puts the legal share at 56 percent in the first half of 2025 and 53 percent in the second.

The appropriate comparison is therefore 56 to 53, using the revised series. A change between published headline numbers can reflect a correction to the measurement as well as a change in the market.

Why More Countries Still Do Not Produce a Global Total

The international chart broadens the view to twelve countries under one commercial model. The monetary cases add the United States and show how national evidence compares. They also reveal why country totals cannot simply be combined: the US figure covers online slots and table games, Norway’s denominator includes physical gambling and lotteries, Sweden uses a competitive-market definition, and France and Finland supply historical evidence.

The studies also measure different boundaries. A provider licensed abroad can sit outside a domestic licensing system without every transaction necessarily being unlawful. H2’s offshore category is broader than a count of wholly unlicensed businesses. Even where the term “illegal” is justified, unidentified sites and activity beyond a model’s reach remain uncertain.

The global H2 estimate and the country studies therefore answer different questions. A sound assessment reports their values, definitions and disagreements. It does not add incompatible amounts or convert an unweighted average of country percentages into a world market share.

What to Ask of the Next Headline

In an April 2026 update, the Gambling Commission described its web-traffic estimates as more useful for understanding trends than absolute volumes, while acknowledging activity outside the data’s reach. A clearly stated limitation is valuable information for the reader.

Five questions help turn a market-size claim into something that can be assessed:

1. What is being counted? Look for the actual unit: people, accounts, visits, stakes or revenue.
2. What is the denominator? Check the country, period, products and treatment of people using both licensed and unlicensed providers.
3. What was observed, and what was modelled? Separate reported operator figures from survey responses, estimated traffic and assumptions that convert engagement into money.
4. What could the method miss? Ask about apps, unidentified providers, sample size and the sensitivity of the calculation to its assumptions.
5. Does the evidence support the conclusion? Check for revisions and distinguish a measured change from an explanation of why it happened.

These questions apply to research commissioned by businesses and to official statistics. Funding and institutional interests should be disclosed; the quality of the evidence still has to be examined.

For an operator assessing a market, a regulator evaluating policy or a reader judging a warning, the useful result is an estimate whose meaning and limits are clear. A high licensed share of players does not settle the question of where money goes. A lower revenue share, by itself, does not establish which policy caused it. Both can inform the debate when the underlying questions remain visible.

Further Reading & Key Sources

• H2: global gambling market update, April 2026; 2024 global online split.
• H2 for Responsible Wagering Australia: Australia Offshore Market Analysis 2025, November 2025; pp.13 and 40–41.
• Blockchain Research Lab for GGL: online black-market study, 2024 revenue model, Table 25 and footnote 42.
• Lotteritilsynet: channelisation report, March 2026, 2025 estimates, pp.20–25.
• The Innovation Group for AGA: illegal-market research, August 2025, online slots and table games section.
• KKV: online gambling outside the monopoly system, 2023 report, 2021 estimates, p.27.
• H2: UK offshore betting and gaming update, May 2026; separate charts for stakes and gross yield.
• Kansspelautoriteit: spring 2026 monitoring release, 16 April 2026.
• Ksa: Monitoringsrapportage online kansspelen, voorjaar 2026, particularly sections 2.1 and 3.1–3.2.
• Ksa: chart data accompanying the spring 2026 report, corrected monthly illegal-GGR series for January–December 2025.
• PwC for ANJ: study of illegal online gambling in France, December 2023, section 7 on the 2023 GGR estimates.
• Ksa: search-volume methodology for estimating the illegal market, particularly sections 3 and 6.
• Dutch government: parliamentary response on online gambling monitoring, letter dated 1 June 2026, section “Marktomvang en vergunningen”.
• Spelinspektionen: Kanaliseringsgrad på den svenska spelmarknaden 2025, 15 June 2026, sections 2–4 and conclusions.
• Gambling Commission: comparisons of different methodologies and channelisation rate approach, November 2025.
• Gambling Commission: update on trends and data approach, 21 April 2026.

Research note: Sources checked on 13 October 2026. The international comparison contains twelve 2024 H2 model estimates; the US is a separate case. Global offshore revenue is our US$293bn minus US$132bn calculation. Germany, Norway, the US and Finland include totals or shares calculated from the cited inputs. Industry-commissioned research is identified beside the figures. Dutch totals are iGaming Review’s sums of the Ksa’s corrected monthly estimates: €475.9 million for January–June 2025 and €527.7 million for July–December, approximately €1.0 billion for the year. The same workbook’s licensed annual total is €1.201 billion; combined revenue is approximately €2.205 billion, giving an illegal share of approximately 45.5 percent. The Swedish amount is our calculation from the regulator’s rounded 84 percent licensed share and SEK 18.7 billion licensed competitive-market net revenue. Neither calculation is a new market model. France’s range is the study’s estimate for 2023; its 20–34 percent comparison uses licensed online revenue from 2022. Different scopes and periods prevent a combined total.

Related reporting: Heather Wardle on independent evidence and the challenges of gambling research.