Every soccer betting line represents a price that can be analysed by economists. These betting lines are essentially stock prices, as they represent traders’ publicly available forecasts. Assuming the efficient market hypothesis is true, these prices will include all the information available, and hence there will be no strategies that can be used to gain an edge over the bookmaker.

The top 5 leagues in Europe provide an ideal example. While they are all the same sport, they have very similar rules. However, they vary in terms of the amount people bet on them, how balanced they are, and how many goals are scored. This essay will argue that soccer betting is very efficient overall but varies between leagues. The market structure of each league means that inefficiencies occur in different areas, but generally they are very small. Also, this essay was motivated by my passion for the beautiful game.

Betting odds can be seen as a form of probability forecasting. The lower the odds, the more likely the market thinks an outcome will happen. Bookmakers will always apply slight price increases to give themselves an edge. This gives the bookmaker their profit.¹ Like any other price, it will respond to competition. A study into 6 large bookmakers shows that the average margin across the Premier League has gone down from 9% to just 4% between 2005/06 and 2017/18. Much of this can be attributed to the rise of betting exchange sites like Betfair.²

The most well-documented inefficiency is favourite-longshot bias. Bets on longshots produce losses per dollar.³ Buhagiar, Cortis and Newall confirmed this using 163,992 odds from 10 European leagues.⁴ Another study found almost all 10 leagues showed favourite-longshot bias in 47,022 matches.⁵ However, Hegarty and Whelan found that this does not occur in Asian handicap markets, meaning the structure of your bet will affect its efficiency.⁶

The Premier League receives the most bets globally and is therefore likely the most efficient. With such a high volume of bets and competition from exchanges, margins are at around 4%.⁷ Professional punters will correct any inefficiencies quickly. However, casual punters will still bet on the most famous teams. In 2022/23, Arsenal received over 41% of bets to win the title but ended up finishing second to Manchester City.⁸ However, the odds on individual matches are rarely incorrect for long. Therefore, speed is key to getting an edge in the Premier League. As the odds change with team news and injuries, a good test of your skill would be if you are receiving better odds than the final odds. Just like a large company’s stock, this market rewards new information.

The presence of giants in La Liga has made this market interesting economically. Forrest and Simmons found that supporters of the most popular team received better odds when placing over 3,000 bets on the Spanish top flight.⁹ This is due to competition between bookmakers. Bookmakers will try to gain the largest fan bases by improving their odds. Along with favourite-longshot bias, this shows that short-priced popular favourites may be a good strategy to use. However, this study was carried out in 2008, and a strategy with such a well-known edge may have now been competed away. In addition, the number of goals scored has dropped from a high of 2.94 per game in 2016/17 to just 2.62 in 2024/25, meaning models based on older seasons may overestimate goals.¹⁰

Serie A had the lowest number of goals scored (2.56) of the 5 leagues in 2024/25.¹¹ However, Marco Rossi found that odds on Serie A do a good job of predicting results but still suffer from favourite-longshot bias. They also found that this bias became more pronounced in matches that had been rigged.¹² This supports the theory provided by economist Hyun Song Shin. Bookmakers who fear they may be at a disadvantage to insiders with more information will give worse odds on longshots. Due to the low number of goals, the most natural markets to model would be draws and low-goal games. Overall, this demonstrates how asymmetric information affects betting. If some punters know the results, everyone else will pay for this by receiving worse odds. This is similar to a high bid-ask spread on a thinly traded stock.

The Bundesliga has the highest number of goals scored of any top league in Europe, averaging 3.14 goals per game in 2024/25.¹³ Over the last 2 decades, they have averaged 2.96 goals per game. In 2020, they were the first major league to return following the shutdown of the pandemic. They played in empty stadiums, meaning there was less of a home advantage.¹⁴ Meier, Flepp and Franck found that bookmakers and exchanges still overvalued home teams. This meant that a strategy could be created using this inefficiency to gain a positive net payoff for over a month. This shows how edges can be found when the world is changing quicker than our models can keep up with. In normal seasons, the Bundesliga has a high number of goals, meaning the over/under goals markets are the best place to test your model.

Ligue 1 is the most unbalanced of the 5 leagues. Paris Saint-Germain won their 5th consecutive title (their 14th overall) in 2025/26. Before the start of the season, PSG were huge favourites to win the title according to bookmakers. There has also been a large increase in goals scored. In 2005/06 they scored 2.13 goals per game, but now in 2024/25 they are scoring nearly 3 goals per game, the most since 1978/79.¹⁵ Ligue 1 does not receive as much global attention, meaning there should be slightly higher margins. Karl Whelan found that the most high-profile leagues have the lowest margins of the 22 leagues in Europe. The structure of the market means that when there is a mismatch, favourite-longshot bias means you should not bet on the underdog. However, Asian handicap betting does not show favourite-longshot bias, meaning this provides a fairer way to bet.

Overall, there is evidence that soccer betting is mostly efficient. The odds do a good job of predicting the outcome. Any inefficiencies such as favourite-longshot bias, fan bias and slow reaction to shocks are very small compared to the margin charged by bookmakers. Often any strategies that can be made using these inefficiencies are only marginally profitable. Bookmakers are the sure winners. Hegarty and Whelan show that they make their highest profits from longshots, showing there is little competition in this area.

This shows how betting can be a good case study to learn from. It demonstrates how information is aggregated into prices, how competition leads to low margins, and how asymmetric information leads to high margins. Overall, your betting slip on a Saturday afternoon can teach you a little about how all markets work.

Notes

1. https://en.wikipedia.org/wiki/Mathematics_of_bookmaking ↩
2. https://ideas.repec.org/h/elg/eechap/16946_3.html ↩
3. https://cepr.org/voxeu/columns/forecasting-soccer-matches-betting-odds-tale-two-markets ↩
4. https://wrap.warwick.ac.uk/id/eprint/101329/ ↩
5. https://kops.uni-konstanz.de/handle/123456789/44938 ↩
6. https://cepr.org/voxeu/columns/forecasting-soccer-matches-betting-odds-tale-two-markets ↩
7. https://ideas.repec.org/h/elg/eechap/16946_3.html ↩
8. https://www.gamblinginsider.com/news/21354/sportradar-mixed-fortunes-as-haaland-and-arsenal-generate-most-premier-league-bets ↩
9. https://ideas.repec.org/a/taf/applec/v40y2008i1p119-126.html ↩
10. https://footballedgelab.com/la-liga/seasons ↩
11. https://sportradar.com/content-hub/news/sportradars-98000-goal-analysis-reveals-europes-most-exciting-soccer-league-for-the-fans/?lang=en-us ↩
12. https://iris.uniroma1.it/handle/11573/445612 ↩
13. https://sportradar.com/content-hub/news/sportradars-98000-goal-analysis-reveals-europes-most-exciting-soccer-league-for-the-fans/?lang=en-us ↩
14. https://www.crsa.uzh.ch/en/news/Are-Sports-Betting-Markets-Semi-Strong-Efficient-Evidence-From-the-COVID-19-Pandemic.html ↩
15. https://ligue1.com/en/articles/l1_article_2627 ↩