A prop is a total with one player inside it.
A prop is not a different kind of wager. It is the same over/under machinery aimed at one player or one event instead of at the scoreboard, and that single change does two things at once. It makes the numbers softer, because no book can price hundreds of individual players as carefully as it prices a handful of sides. It also makes them more expensive, because the margin on a prop runs routinely about 40 percent wider than the margin on a main line, and close to double it at the worst pricing. This page covers the structure, what that extra margin costs you, and the one piece of prop evidence almost everybody reads backwards.
Markets that ignore the final score
A prop bet, short for proposition bet, is a market on something other than the result of the game. The most common kind by far is the player prop, which sets a number for one player's output and lets you take either side of it: passing yards in football, rebounds in basketball, strikeouts for a starting pitcher in baseball. The structure is an over/under aimed at one player rather than at the scoreboard.
Two other families sit beside it. A game prop prices an event inside the game rather than its result, such as which side scores first or which team leads at the half. Those are not reliably two-way markets, because a half can finish level and a first-score market needs somewhere to put a scoreless one, so a book either quotes a third outcome or writes a rule that voids the bet. A yes-or-no prop carries no number at all, only a threshold that is met or it is not. Plenty of those are quoted on both sides, such as whether a game reaches overtime, and they behave like any other pair of prices. The ones to be careful with are the single-sided fields: a book lists a price on each player to score the first touchdown and no price at all on the far likelier outcome that a given player does not, and with nothing to pair a price against, the margin cannot be read off the screen.
One structural detail separates a player prop from a side or a total: it settles on the official statistics rather than on the scoreboard. Whether a ball is scored a hit or an error, and whether a loose ball is credited as a player rebound or a team rebound, are judgements made by a scorer, and either can decide a ticket that finishes level with the number. Books also differ on whether a statistical correction published after settlement reopens a market, so the house rules are the thing to read before you take a prop that sits one event away from going either way.
The same structure at a wider price
Take a placeholder player prop set at 6.5 with -115 on the over and -115 on the under. Convert each side the usual way, 115 divided by 215, and each one implies 53.49 percent. The two together sum to 106.98 percent, which is 6.98 points more than can actually happen, and that surplus is what leaves the book a hold of 6.52 percent of everything staked on the market. How an overround turns into a hold is derived in full on our page about juice.
Now set it against standard main-market pricing. Two sides at -110 imply 52.38 percent each, sum to 104.76 percent, and hold 4.55 percent. The prop keeps about 43 percent more out of the same stake, because 6.52 divided by 4.55 is 1.43. Props quoted -120 on both sides are common too, and there each side implies 54.55 percent, the pair sums to 109.09 percent, and the hold reaches 8.33 percent, which is 83 percent more than the main-line figure and close to double it. The structure has not changed at all, only the price attached to it.
The version of that worth carrying around is the win rate, because it is the only unit that compares directly to your own opinion. A -110 side asks you to be right 52.38 percent of the time, a -115 prop asks 53.49 percent, and a -120 prop asks 54.55 percent, which is 1.11 and 2.16 percentage points of extra accuracy demanded before a penny comes back. Those figures sound small and are not: at -110 the whole distance between breaking even and a 5 percent return is about two and a half points of win rate, so the worst prop pricing is asking you to hand over most of a winning edge before the wager is placed.
Seven of ten, and what it actually counts
The most quoted piece of evidence in prop betting is a hit rate: a player has gone over in seven of his last ten. Before it can carry any weight you have to know which of two things it is counting, because prop screens publish both and rarely say which. If it counts results against the number posted in each of those ten games, it is the right question asked at a sample far too small to answer it, because seven or more from ten coin flips comes up 176 times in every 1,024 sequences, or 17.2 percent of the time. If it instead applies today's 6.5 to his last ten games, which is the other common presentation, then the record is showing you form the market has already absorbed, because the line was walked up from 4.5 to 6.5 by the very games being counted.
The second half of the trap is a unit problem. A prop is quoted per game, but the thing that actually produces it is opportunity: per snap in football, per plate appearance in baseball, per minute on the floor in basketball. If a rotation change cuts a basketball player from 30 minutes to 24, a fifth of his opportunity has gone before anyone forms a view about how well he is playing, because 24 divided by 30 is 0.8. Every per-game figure in his history was compiled under the old arrangement, and none of it has been restated.
That is why role news outranks form on a prop, and why props punish stale evidence far harder than team markets do. A hitter moved from second in the order to seventh comes to the plate fewer times in the same nine innings. A backup pressed into a starting job in football plays a snap count his own history never contained. The same news barely disturbs a game total, because the rest of the team absorbs it, while a player prop has nothing to absorb it with.
Read the price before you read the player
Convert both sides of the market first, write down your own estimate of the underlying rate second, and open the game log third. The first step is what tells you which question you are being asked, because a view on a player is not yet a view on 6.5 at -115. Reading a price is not the same as adopting it, though, and that distinction is the whole of the rule: a posted number is a powerful anchor, so your estimate has to be on paper before any history is opened, or the log will quietly agree with the line and hand you the book's opinion back under your own name. In that order the history becomes a check on your figure rather than the source of it. The full step-by-step version is in how to research a player prop.
Then shop props harder than you shop sides, and shop the number before you shop the price. Books project each player themselves rather than pricing off a consensus, so on a prop they disagree about the number itself and not only about the cents attached to it. Half a point is also a far larger share of a small number: 7.7 percent of a 6.5 prop against 1.1 percent of a 45.5 football total. Share of the number is not share of the probability, so read that as a direction rather than a multiple, but the direction is real, because the spread of possible results around a small counting stat is much tighter than the spread around a football score, so the same half point crosses more of it. What shopping is worth across a season is covered in line shopping.
Pick'em apps belong in the same search. PrizePicks and Underdog post one number per player with no price attached to either side, so there is nothing to de-vig and no implied probability to read off the screen. Both directions pay the same, which is the app asserting that its number is a coin flip, and that leaves the number itself as the only thing there is to shop. A full point of difference between an app's number and a sportsbook's is worth more than the ten cents of price most people spend their evening hunting. Our pick'em optimizer sets an independent projection against the number an app posts, and the prop trends board charts how a posted line and its price have moved, so the number in front of you gets checked against something rather than taken on trust.
The market that quietly multiplies your tickets
A normal slate carries hundreds of props, and each one is a separate wager that takes a few seconds to add. Put the two costs side by side: the wider margin takes about two cents more out of every dollar staked than a main side does, a factor of 1.43, while a board that size makes it trivial to run three or four times as many tickets as you would on game lines, so the count is the larger multiplier by some distance. Decide how many prop wagers a night you are willing to place before the board is open, and hold it as a fixed number rather than a feeling. If the count climbs anyway, the deposit limits, time-outs, and self-exclusion tools listed on our responsible gambling page are worth using early rather than late.
Prop bets, answered
What is a prop bet?
A prop bet, short for proposition bet, is a wager on something other than the final result of a game. Player props post a number for one player's production and offer an over and an under on it, game props price an event inside the game such as which side scores first, and yes-or-no props settle on whether something happened at all. The game still decides the ticket, but only one line of the box score matters.
What is a player prop?
A player prop takes a single line of the official box score and turns it into an over-under, so the wager is settled by one player's own figure and not by the scoreboard. The sportsbook posts a number, such as passing yards in football, rebounds in basketball, or strikeouts in baseball, and the wager is graded on where that one figure lands against it. Because a single player generates the result, opportunity decides these markets before performance does, so a change in snap share, batting order, or rotation minutes moves a prop while the game line barely notices.
Why do props carry worse prices than sides and totals?
A prop is priced off a projection of one player rather than off a market of bettors, it goes up later than the game line, and the money that arrives on it is too thin to sharpen it, so the book protects itself with a wider margin. Two sides at -115 leave a hold of 6.52 percent and two sides at -120 leave 8.33 percent, against 4.55 percent on a standard -110 side. Those extra points are what a book charges for a number nobody has stress-tested yet.
Are player props easier to beat than main markets?
Prop numbers are softer than main lines, because there are hundreds of them on a slate and each one gets a fraction of the attention a side gets, so a genuine mispricing survives longer. The wider margin pushes in the other direction at the same time. Props are easier to beat only when your edge is large enough to clear the extra cost, which is a higher bar than the same read would face on a spread.
What is an alternate line on a prop?
An alternate line is the same prop offered at a different number, with the price adjusted to match. Moving the number moves the two sides in opposite directions, so a lower number is a heavy minus price on the over and a plus price on the under, while a higher number is the reverse. An alternate lets you bet the size of an outcome and not only its direction, though the margin on them is usually wider than on the main number, so the number you move to has to be worth the price attached to it.
Can a player prop push?
A prop pushes when the posted figure is a whole number and the player finishes exactly on it, and the stake comes back. The risk is larger than it is on a scoreboard market rather than smaller: a receptions line at 4 or an assists line at 6 is a small integer, so finishing level with it is an ordinary result rather than a remote one, which is why a whole-number prop needs a better read to be worth the same money. It is also the settlement where a scorer's ruling can decide the ticket, since whether a play is credited to a player at all is a judgement rather than a reading of the scoreboard.
Why do prop lines differ so much between sportsbooks?
Each book projects the player itself rather than pricing off a consensus, posts the market later than it posts the game line, and accepts smaller wagers on it, so there is far less money pulling the numbers into line with each other. One book at 6.5 and another at 7 on the same player is an ordinary sight rather than an error. That is a different situation from a main side, where books agree on the number and differ only in the cents attached to it.
What happens to a prop if the player does not play?
A player prop is normally voided as no action when the player takes no part in the game, and the stake is returned. If that prop was one leg of a parlay, the parlay is repriced on the legs that still stand. Partial participation is the grey area, since a player who appears at all usually leaves the wager standing, and each book's house rules state where its line sits.
Bring your own number to the prop board
Our prop trends board charts how a player's line and the market's price have moved over time, next to how that player has finished against the number, so the hit rate you are reading arrives with the context it needs.