Dutching is a betting strategy that involves placing bets on all outcomes of an event and due to odds discrepancies between Sportsbooks, a level profit can be made no matter what the outcome is.
Most sportsbooks nowadays are run using feeds and there are very few that actually odds compile. This inevitably means that most Sportsbooks offer very similar product, with similar odds. You could almost say that a marketing war has been evident in the last few years in order to secure new signups and retain customer loyalty to their brands. In order to stand out from the crowd, Sportsbooks might enhance certain odds and take a some risks and views as to who they might think will win a match and allow (up to a certain level) some business that would not be classified as recreational gambling. While taking risks of offering dutching situations might be great at boosting numbers in the short-term, it is not a long-term strategy to run a successful sportsbook operation.
Maths/Logic behind Dutching
The basis of Odds Compiling which you can read about here will explain how overrounds work but simply put, if we were to toss a coin, the likelihood of the coin landing on heads or tails would be 50% each.
To convert this to odds the simple calculation of: 100 divided by % chance of it happening. Therefore the odds for a coin toss would be 100/50 = 2.0 for heads and 100/50 = 2.0 for tails. To try to make a profit, Sportsbooks will add overround to the odds.
Dutching positions occur when you add up the likelihood of all selections happening, the answer is less than 100% We call this position under-round.
Dutching in action
Let’s presume we have a tennis match between player A and player B with these odds from Sportsbook 1 and 2.
Player A Player B
Sportsbook 1 1.70 2.10
Sportsbook 2 2.10 1.70
Judging by the odds it is quite clear that Sportsbook 1 believe that player 1 is the favourite to win the match while Sportsbook 2 think that Player B is the favourite.
Given this situation, should the punter bet £/€100 on player B with Sportsbook 1 and £/€100 on player A with Sportsbook 2, whatever the outcome, £/€10 will be won by the player. It is very important to point out here to always make sure that the market rules are the same for both Sportsbooks.
Here is another example in a 3 selection situation:
Odds Stake Winnings less Losings End result
4.0 50 150 – 60 +90
5.0 40 160 – 70 +90
10.0 20 180 – 90 +90
Technically in the example above, you can calculate the under-round by doing: 100/4.0 = 25 + 100/5.0 = 20 + 100/10.0 = 10.0. The total for the ‘book’ is 55, meaning a very high level of under-round and an extreme situation.
Last tip, keep an eye out for large tournaments or special events as more dutching opportunities can happen!