Sports betting: Bet singles, multis or both?

So many sports bettors, especially hobby punters, create betting slips with many games combined. Doing this they get bigger odds when they win, but does it pay long-term?

The short answer to the question in this article, if you have limited time:
If you want to bet seriously on sports, "invest" rather than "gamble", with the aim of creating a profit over a long period of time: Play singles (just one match on the betting slip) rather than multis (two or more matches on each betting slips). Good luck!

Below is the longer version of the same answer. This blog post is written for people new to sports betting or with a desire to learn more.

"Guy won $55.000 on crazy betting slip"

The bookmakers are good at letting everyone know each time one of their clients have cashed a "crazy" winning bet slip with many games combined and huge odds. That's because these coupons are called crazy for a reason; bookmakers love them because they make lots of money from them, even with the occassional big payout which then can be used in marketing.

You have to ask yourself: Why do so many betting companies advertise their big loss on one particular betting slip with a low stake and huge odds?

The answer is of course that they make lots of money from such "impossible" betting slips as they so rarely win. A few big payouts each year is nothing compared to the money these slips earn the bookmakers.

Of course, there's nothing wrong in betting on multis with huge odds; you're staking your own cash and you can do with it as you please. If dreaming of a big payout is your kind of Saturday entertainment, a crazy betting ticket is a cheap way of having fun.

Fun aside, it could be useful to know what actually pays better in the long run if you are looking to bet on sports in a more serious manner. Singles or multis?

First: A few definitions

Sports betting

To cover the basics: Sports betting using odds is all about calculating probability.

For example - let's say we want to bet on a football match. The bookmakers calculate a probability for a home win, a draw and an away win. This is the base calculation for creating odds, whether they are just win/lose, handicaps etc.

These probabilites are adjusted slightly to create an advantage for the bookmaker and then calculated as odds offered to betting clients.

As a sports bettor your job is to better at calculating these probabilities than the bookmakers. To be more exact, to spot errors in their odds.

The bookmakers have the advantage of adjusting their odds in order to tip them in their favour, mathematically. But they have to offer odds on all matches in all tournaments in all sports (almost). Your advantage is that you can pick that one match where you think they are mistaken, and bet on it.

There are other mechanisms in odds betting as well, especially in how the betting markets function and how odds are adjusted according to the flow of money on the various outcomes.

Playing singles means that your betting slip only has one outcome in one game or tournament. If that wins, you collect your stake multiplied with the odds taken.

Multis / multiple selections / accumulators / parlays / combo bets
When you place a bet such as this you are playing multiple bets on different events, and all need to win. This means higher odds as the odds for each bet is multiplied before multiplying with your stake. It also means higher risk. Bookmakers in general prefer clients who play accumulators.

Payout percentage

This is the bookmaker's advantage when creating odds. In order to increase their chances of making money and decreasing the chance of costly errors, the bookmakers allow themselves a bit of extra margin when they calculate probabilites.

For example the payout percentage offered could be 95%, which means that the bookmaker has given themselves an average advantage of 5%, while they expect to pay back 95% of the money collected from sports bettors as winnings.

Betting on singles

Whenever you're betting on singles you will on average win the payout percentage each time. Of course, if your bet loses you lose your entire stake, and if it wins you win your stake multiplied with the odds. But on average, you will lose 5% of your cash on every bet.

If you are better at calculating the probabilities of certain events than the bookmaker, you can increase this percentage to 100% (which would be break even) or even higher; of course that's when you start making money long-term from sports betting.

Betting on multis

If you play three games combined in a multi, you wil on average win 0,95% * 0,95% * 0,95% = about 86% of your stake. Suddenly the bookmakers have increased their advantage from 5% to 14%. Your expected return is smaller, the bookmaker's is bigger.

This means that for every extra match you put on your betting slip you reduce your expected payout percentage. In addition there's the psychological effects of winning more seldom and also seeing good bets being ruined by bad ones, such as when three out of your four combined matches win, but the one losing bet ruins your entire bet slip.

What about the world's greatest sports bettors?

Multis are more profitable than singles if you are consistently better at calculating probabilities than the bookmaker.

Despite this, almost all pro gamblers bet singles every time. So should you.