Side Bets Vs. Sports Bets

Side bets are known as a prop (or a proposition) bet in sports betting. It is a type of a side wager for the event or part of it that have little to do with the final outcome of the game. Sides also apply for lottery bets, casino games, especially craps and even poker. A side bet allows for diversification and also gives you the chance to stake without a straight participation in the game!

Gambling language is full of technical and expert terminology, and the jargon in this niche is also “bushy”. With such a rich vocabulary, for a beginner in gambling it may be difficult to get familiarized with the games and their rules, as well as to understand how this industry really works, when relying on descriptions and guides where the terms are poorly defined or explained. The language associated with the betting sector is complex as well. For instance, its core term, that of ‘bet’, acquires various meanings in different contexts: we have sports bets, casino bets, simple and combined bets, base bets and side bets.

In this article we will clarify what a side bet is and what are the resemblances and differences between side bets and the better known sports bets.

Betting and gambling

Is there any distinction between gambling and betting? Most of the players and experts admit that betting is a form of gambling, which has many other different forms, such as casino gambling or playing poker, or even playing other house or street games of chance.

But this genus et differentia distinction becomes questionable if we take every play of a game of chance to be a bet itself. A bet can be defined in general as consisting of a stake associated with an event producing uncertain outcomes. It is actually something that you buy (either product or service are valid categories for such thing) – you actually buy the right to participate to that event by predicting its outcome and such prediction may be loosing or winning.

When you fill in and buy a ticket from a bookmaker you obviously place a bet, in the literal sense. But you make essentially the same kind or purchase in a casino game: When you place your chips on the roulette table, you make a bet predicting what (kind of) number will come out on the spin; when playing blackjack, your bet is that you will beat the dealer; in slots, inserting a coin or credit is also a bet that you make. The game of poker consists of a succession of bets – at every hand or stage of the game you place your stake into the pot and your prediction is that you will win the game.

Mathematically speaking, a bet is an ensemble of three elements: a predicted event, a stake, and a payout rate. With respect to this abstract definition of a bet, gambling is equivalent to betting.[1]

Another distinction is usually made between gambling and betting by those considering betting as involving some minimal skills with respect to prediction, while seeing gambling as only associated with casino games, whose outcomes are entirely random and unpredictable. The skill element as responsible for a distinction is something that is worth considering. An argument supporting this distinction comes from the distinctions we can make if we focus on the first element of a bet’s triad, namely the predicted event.

Base Bets and Side Bets

In everyday life we can bet on almost every possible event, provided that there is someone who will accept our bet. You may bet that a certain candidate running for president will win the election, but you can also bet as well on the number of people who have voted. Of course, there is a causal relationship between the two events – the result of the election depends on the number of electors, but on other factors as well, like the skills of the candidate in their campaign. This relationship has only one causal and temporal sense – from the latter to the former, and not vice versa; winning the election cannot influence the number of people voting, nor preceding this event.

Now imagine you are in a casino watching a blackjack game. You may either participate in the game to beat the dealer, or stay aside and place a bet on the cards that are dealt. For instance, you may bet that a player is dealt a mixed pair (two cards of the same value but different suit and color). If you win this latter bet, you are paid 5 to 1.

Now, what are the basic differences between the two betting options? As a blackjack player, you may use your skills to win the game, conditioned also by the luck factor, which reverts to the cards you are dealt randomly. As a watcher betting on the outcome of card dealing, you don’t use any skills and make a prediction based on chance only. The payout for this latter bet (5 to 1) is different from the payout you would get as a winning player (1 to 1 or 3 to 2 if you win with blackjack, in the classical version of the game). The final outcome of the game (who wins) will not affect the watcher’s bet.

The same stands for the election bet in the previous example: if you bet on who will win the election, you may use some skills and knowledge, while if you bet on the number of voters, there is mostly luck involved if your prediction comes true.

The watcher’s bet is called side bet and the player’s bet is called base bet (or main bet).

As a formal definition, a side bet is an optional bet on a technical event that determines the final outcome of a game, for which the bettor does not participate as a player in the game, and whose payout is not included in the main payout schedule of the game.

Side bets in casino games and poker

The popularity of the classical casino games and poker variants resulted over time not only in many versions of these games, but also in side bets associated with them, offered by the casino; sometimes they are called proposition bets.

Casino Side Bets

For example, in blackjack there are several side bets offered, of which the most popular are the insurance side bet, the perfect pair (mixed, color, or perfect matched), and the 21+3 bet. All these bets are made on the outcome of the card dealing, that is, the card configuration in the player’s and dealer’s hand after the initial dealing (two cards for the player and the face-up card of the dealer). The 21+3 side bet comes in different options and is inspired from poker. For example, the Flush 21 + 3 bet is placed on the possibility of the three cards dealt to be of the same suit and pays 5 to 1.

In baccarat, there are many more side bets available than in blackjack and each version of baccarat has its own palette of side bets. Like in blackjack, side bets concern the card configuration on the table (for the Banker’s and Player’s hands, in this case). For example, a baccarat side bet is Panda 8, commonly offered in EZ Baccarat. It assumes betting on the Banker’s hand achieving 8 points with three cards and pays 25 to 1.

If we take in-depth look on how baccarat works, we can say that this game is itself a side bet, since the Banker and the Player are actually fictional – there are two separate hands operated by the dealer, so when you bet on one or the other you actually bet on the final card configuration on the table.

How about craps? Craps mostly consists of side bets. Any bet placed by a bettor who is not the shooter is a side bet and there are plenty of such bets available in this game. For all casino games offering side bets, these options are marked on the game’s table, so actually they are integrated in the main game.

Casino side bets are a way of making the games more attractive by diversification. This means extending the wagering options and giving the bettor the possibility to bet without a straight participation in the game. The payout odds of the side bets are in general higher or far higher that those that the main payout schedule of the game offers. But this is just an apparent advantage compared to the base bets, because the probabilities of those events that the side bets are placed on are generally low. As a result, the house edge of a side bet is usually higher than the house edge of a base bet.

Poker Side Bets

The game of poker, reaching an outstanding popularity over the last two decades, came to have its own side bets. The major online poker platforms and poker tournaments offer the audience the possibility to place side bets in regard to the outcomes of the games, not only in what concerns the winners, but also the card configuration of the board. You can bet that a particular color is dominant on the flop, or the board is of the same color, and so on. As in casino games, poker side bets have their own payout odds.

With side bets offered, the poker platform or tournament turns itself into a bookmaker.

Lottery side bets

While casinos incorporated side bets into their games and betting options, bookmakers could not stay away from this product, as long as the diversification of betting markets and options is a primary marketing goal for them.

From the bettors’ standpoint, a side bet on whatever event may be perceived as a tasteless and odorless bet, especially for those who bet regularly on sports. Indeed, the use of skill and the whole “private investigation” preceding the prediction in sports betting is part of the beauty of the game for sports bettors. In side bets, they can only bet on pure chance, however side bets offer other advantages, like the statistical ones.

It seems that at this moment the only type of side bets offered by the major bookmaker companies is the lottery side bets. There are isolated sportsbooks offering also poker side bets associated with the major poker tournaments, so the inclusion of poker side bets as a betting market is marginal.

In lottery betting you bet on events taking place at state lotteries. You can bet on any number or several numbers in the range of that lottery matrix. Unlike participating in the lottery, where you choose (and as such bet on) a combination of numbers of a required size, in a lottery side bet you don’t choose combinations, but numbers. You may choose from one number to the number of numbers being drawn. For instance, at a 5/40 lottery you may bet on one, two, three, four or five numbers of your choice from all 40. The bet is winning if all the numbers you chose are drawn and each such bet has its own payout odds.[2]

Lottery is known as the game of chance offering the lowest winning odds among all games of chance. They say that is more likely to get struck by lightning than winning the lottery with the jackpot or top prize and I don’t have any reason to doubt that this is the case. With a lottery side bet you have the chance to bet against higher odds, by reducing the number of chosen numbers.

For example: At a 6/49 lottery (one of the most popular), the probability of guessing all 6 numbers to be drawn is 1/13,983,816; guessing five numbers is 1/54,201; and guessing four numbers is 1/1,032.

A lottery side bet at a 6/49 lottery will allow you to choose one number (probability of guessing about 1/8) or two numbers (probability of guessing about 1/78), for which the winning probabilities are decent compared to those astronomically low numbers in the real lottery. Yet the payout is not that high compared with the real lottery. For the one-number bet, bookmakers usually offer around 7 to 1 payout odds (and around 75 to 1 for the two-number bet) in the 6/49 lottery, for ensuring their house edge. Besides, in lottery side betting there is no jackpot accumulating from other players’ sales, as in the real lottery.

Side bets or sports bets?

When choosing a type of bet or another, bettors use various criteria, of which most are subjective, associated with their interests, hobbies, habits, and the entire activity associated with the preparation of the bet. No matter we talk about subjective or objective criteria of choosing, bettors have to know what precisely are the differences between side bets and sports bets with respect to their entire action of betting and the bet itself, for making informed choices:

Sports bets
  • The likelihood of the predicted event is estimated basing on a combination of deterministic and statistical information and not as a mathematical probability.
  • The prediction is based on the bettor’s own analysis and investigation.
  • The payout odds may fluctuate as the event approaches, based on the bookmaker’s analysis and the bettors’ choices.
  • Events span all sports.
Side bets
  • The likelihood of the predicted event can be computed precisely as true odds (probabilities).
  • No analysis is required other than computing the probability.
  • The payout odds are fixed.
  • Events span lotteries and poker.

We can see that the above features are mostly complementary between the two types, which apparently render the choice straightforward. However, it is known that it’s in a gambler’s profile to diversify their gambling activity, markets, and options. For a regular sports bettor, experiencing the side bets may be also a means to acquire new knowledge in the field of applied probability and statistics, which counts to their gambling expertise.

With the current tendency of a fast development and diversification for the betting industry, it is expected that in the near future side bets will come to cover events in other domains beside lottery and poker, perhaps sports, too.

Now that we saw what side bets are and what are the resemblances and differences between them and the more popular sports bets, we may come back to our initial question of whether there is a distinction between gambling and betting. The skill/chance balance present in the distinction between sports bets and side bets, as well as the participating/non-participating features, can account for a distinction between gambling and betting that can be extended beyond the industry.

After all, life is uncertain as the outcomes of the games are. With every decision we make in daily life we take a bet and such choices are informed and reasoned, since we care about the effects more that we care if we loose some money occasionally by betting on football. This is why we like to bet rather than gamble in daily life and enter a casino sometimes if we need the latter.


  • 1. Barboianu, C. (2022). Understanding Your Game: A Mathematician’s Advice for Rational and Safe Gambling. PhilScience Press.
  • 2. Barboianu, C. (2009). The mathematics of lottery: odds, combinations, systems. Infarom.

Catalin Barboianu
Catalin BarboianuCatalin Barboianu is an experienced iGaming writer and gaming mathematician. He has written various books and articles about problem gambling and gaming probabilities.