How does sports betting work?

The short answer

A sports bet is an agreement between you and a licensed sportsbook. You stake an amount on an outcome, such as a team winning. The sportsbook quotes a price for that outcome. If the outcome happens, the sportsbook pays you according to the price and returns your stake. If it does not, the stake is lost.

Everything else in sports betting is a variation on that: different outcomes to bet on, different ways to write the price, and different rules for settling. The sections below take them in order.

Step 1: pick a market

A market is the question a bet answers. A single game usually has many of them. The main ones are in this table.

The guide to moneyline, spread and totals compares the three main bets side by side. Articles on moneyline bets, prop bets and parlays go deeper on each.

Step 2: read the price

US sportsbooks write prices as American odds. A minus number is how much you must stake to win $100, and a plus number is how much you win on a $100 stake. Take a game with Team A at -150 and Team B at +130. A $50 stake on Team A wins $33.33 in profit, and a $50 stake on Team B wins $65.00. In both cases a winning bet also returns your stake.

Every price implies a chance. For -110 it is 52.4%. That is the share of bets at that price you must win to come out even. The guide to American odds shows the arithmetic, and the odds calculator does it for you.

Step 3: place the bet

In an app, you tap the price to add it to a bet slip, enter a stake and confirm. The price is locked at the moment you confirm. If the price moved while you were on the slip, the app usually asks you to accept the new one. Before confirming, check three things: the exact market, the price and the stake. A common beginner mistake is tapping the wrong side of a spread or the wrong period of the game.

Where you are matters. Sports betting is legal in some states and not in others, and an app can take bets only from people physically in a state where it is allowed. The state law table shows what we have verified against official pages, and how to bet on an app walks through opening an account.

Step 4: how the sportsbook makes money

The sportsbook does not need to know who will win. It needs the prices to add up to more than 100%. A market priced at -110 on both sides implies 52.4% for each side, which adds up to 104.8%. The extra 4.76% is the margin, sometimes called the vig or juice.

Here is a simple picture of it. Two bettors each stake $110 on opposite sides of a -110 market, so the sportsbook takes in $220. One of them wins and is paid $210: the $100 profit plus the $110 stake back. The sportsbook keeps $10. It collected from the loser a little more than it paid the winner, whichever side won. The explainer on vig and parlays shows this with a moving diagram.

For you, the margin means that a bet has an average cost. If you could pick winners no better than chance, the margin is what you would lose over time. It also means that a bet is worth making only when your own honest estimate of the chance beats the break-even rate of the price.

Step 5: how a bet settles

A bet ends in one of a few ways. It wins and pays. It loses. It pushes, which is a tie with the number on a spread or a total, and the stake is returned. Or it is voided, for example when a game is canceled, and the stake is returned. A few details change the result: some markets count overtime and some do not, and the rules for a player who does not play differ by app and by market. The app shows the rules for each market, and the house rules page covers postponed and shortened games.

Winnings go into your account balance. Withdrawing them follows the app's rules for payment methods and identity checks, which differ from one app to another.

Step 6: parlays and why they are different

A parlay combines several bets into one. Every leg has to win, and the prices multiply. Three legs at -110 with a $20 stake pay $119.16 in profit if all three win, which is a combined price of +596. The chance of winning all three falls fast, because the chances multiply as well. The parlay calculator prices any ticket and shows the average result.

Reading a bet slip line by line

A slip is short, and every line matters. It names the market and the side, such as "Team A moneyline" or "Over 47.5". It shows the price, for example -150. It has a field for the stake. And it shows the amount you would win and the total return. Check that the "to win" figure matches your own arithmetic. For -150 and a $50 stake it should read $33.33 in profit and $83.33 in total return. If it reads something else, you may have the wrong market or a price that moved.

Slips that hold several bets add a line for the combined price. On a parlay that is the number to compare against the single-bet prices, because it shows what the combination really pays.

Losing streaks are normal

At a price of -110 you need to win 52.4% of bets to break even. That means a bettor who is right exactly that often still loses 47.6% of the time. The chance of losing five bets in a row from any given starting point is 2.4%, and the chance of losing ten in a row is 0.06%. Those numbers look small, but over many bets such runs do happen. If you stake $50 a bet, ten losses in a row costs $500. The practical lesson is to size your stakes so that a bad run does not force you to change how you live.

What to compare between apps

Because the same game is offered by several licensed apps, it pays to know what actually differs. The price on the same side is the first thing: even a few cents of difference changes the break-even rate. Next come the markets on offer, since not every app lists every prop or bet type. Then the rules for settling, such as how a player who does not play is handled. Finally, the tools for staying in control, such as deposit limits and self-exclusion, which the state regulator may require. We do not rank individual apps on this site, because we have not verified app-level facts for them, so use the regulator's own list of approved operators to see which apps are licensed where you live.

What a first bet looks like end to end

Say you want to bet on the favorite at -150 with a $50 stake. You open the market, tap -150 and enter 50. The slip shows a profit of $33.33 if it wins. You confirm, and $50 leaves your balance as the stake. The game ends and your team wins, so $83.33 lands in your balance: the profit and the stake. If the team had lost, the $50 would be gone and nothing would come back.

That is the whole cycle. The rest of sports betting is learning to read prices accurately and to keep the size of your bets under control.

Mistakes beginners make

• Treating a bet as a prediction of who wins, when it is a price that needs to be good enough.
• Chasing losses with bigger stakes.
• Stacking many small parlays and losing track of the total staked.
• Skipping the rules of a market, such as how overtime or a player who does not play is treated.
• Betting from a state where the app is not licensed. This is a legal problem as well as a practical one.

A checklist before your first bet

• Is sports betting allowed where you are, and is the app approved there?
• How much can you afford to lose, and have you written that number down?
• What win rate does the price need?
• What happens to the bet if the game is shortened or a player does not play?

Words you will meet

• Sportsbook: a licensed business that takes sports bets.
• Stake: the amount you bet.
• Odds: the price of a bet, written here as American odds.
• Push: a tie with the number, which returns the stake.
• Margin (vig, juice): the amount by which the implied chances add up to more than 100%.
• Parlay: several bets combined, all of which must win.

Keeping it in proportion

Betting should stay entertainment, paid for with money you can afford to lose. Set a limit before you start, keep stakes small and do not bet to win back a loss. If you or someone you know has a gambling problem and wants help, call 1-800-GAMBLER. The responsible gambling page lists tools and help. To practice reading prices before you stake anything, try the odds quiz or the odds course.

Frequently asked questions