--- title: "Over/Under Betting Explained: How Totals Work and What Polymarket's Data Says About the Under" canonical: "https://0xinsider.com/learn/over-under-betting-explained" datePublished: "2026-09-13" dateModified: "2026-09-13" description: "What a total is, how Polymarket prices Over and Under in cents with half-point lines, why the public bets the over, and what 82,080 settled game totals show: the Under hits 52.7% of the time and the price already knows." --- # Over/Under Betting Explained: How Totals Work and What Polymarket's Data Says About the Under Last updated: 2026-09-13 Canonical: https://0xinsider.com/learn/over-under-betting-explained An over/under bet, or a total, is a bet on how many points, goals, runs or rounds a game produces against a number the market sets. This guide covers how the bet works, how Polymarket prices it in cents with a fixed half-point line, why the public is said to bet the over, and what the data says: across 82,080 settled Polymarket game totals the Under hit 52.7% of the time, Under buyers paid two cents more for it, and neither side beat its price. It ends with how to read a game's total on 0xinsider and which side the graded wallets take. ## What an over/under bet is A total is a bet on the combined score of a game, with no view on who wins. The market sets a number, 47.5 points for an NFL game, 2.5 goals for a soccer match, 8.5 runs for a baseball game, 2.5 rounds for a fight, and the bettor takes the Over if they think the game produces more than the number and the Under if they think it produces less. A 3-0 soccer match goes Over 2.5 and Under 3.5; a 1-1 draw goes Under 2.5. The number is chosen so that the two sides are close to a coin flip, which is why totals are the bet where a bettor's view of the game matters more than their view of the teams. Two strong defenses can produce an Under between two good teams; a weak goalkeeper on each side can produce an Over between two poor ones. The team you like is beside the point. At a sportsbook the total moves and the price on each side stays near -110, and the guide at 0xinsider.com/learn/line-movement-sports-betting-explained covers how a moving line works. On Polymarket the mechanics are different, and simpler. ## How a total is priced on Polymarket A Polymarket game total is a market with two outcomes, Over and Under, and a line that is fixed in the market itself. The line is always a half point, so a market cannot push: of 80,848 settled game totals with a recorded line since April 2, 2026, every one carried a .5. Each side has a price in cents, and the two prices sum to about a dollar. Over 2.5 at 56¢ means the market gives the game a 56% chance of three or more goals, and buying it pays $1 a share if it does. The price is the probability, so there is nothing to convert. The cost of the bet is the spread between the bid and the ask, one cent at the median on Polymarket sports markets, plus the sports taker fee, which at 50¢ is 2.5% of the stake and falls as the price rises. A resting limit order pays no fee. The guide at 0xinsider.com/learn/polymarket-fees-explained has the schedule. Because the line does not move, the market's changing view of a game shows up in the price. Over 2.5 opening at 52¢ and trading at 58¢ by kickoff is the same event as a sportsbook moving its total from 2.5 to 3, expressed in probability instead of in goals, and every trade behind it is on a public ledger with a wallet attached. ## The folklore: the public bets the over Every sportsbook bettor learns two things about totals early. The public bets the over, because rooting for points is more fun than rooting for a scoreless game, and because overs sit in parlays more comfortably than unders do. And the book knows it, so it shades the total up a little, which means the under is the disciplined side and the over is the entertainment. Both halves of that are claims about a bookmaker's customers, read from the bookmaker's side of the counter. Some seasons the under covers more; some seasons it does not; and the shading is a half point on a line that is already near the middle of the distribution. It is a lean, and a small one, and it survives because it is plausible rather than because anyone outside the book has been able to measure it. Polymarket has no book and every buy is public, so the two halves can be measured separately: how often the Under actually settles, and whether the price reflects it. The study at 0xinsider.com/research/over-under-polymarket-sports does both, and the next sections walk through what it found. ## The Under settles 52.7% of the time Across 82,080 Polymarket game totals with a kickoff between April 2 and September 13, 2026, and a settled result, the Under hit 52.7% of the time, with a binomial half-width of a third of a point. The numbers Polymarket lists sit a little above where the games land, which is the folklore's premise, confirmed on a market with no bookmaker to shade it. The lean depends on the sport. Soccer, 49,291 markets, went Under 54.3% of the time, and esports 55.3%. Baseball and hockey were coin flips at 49.8%. College football's totals went Under 46.1% of the time and the NBA's 44.7%, so the Over hit more often there. MMA round totals went Under 37.8%: most fights went past the listed number. The chart below has each sport with 500 or more settled totals. A share like this is a fact about lines and results. It tells you which way the numbers sit in each sport. It does not, on its own, tell you whether anyone is paying for the lean, which is the question the next section answers. ## Why that is not a free bet The study scored 45,662 large buys on those totals against their results. Under buyers paid 58.4¢ on average and won 57.9% of the time, half a point short of their price. Over buyers paid 56.4¢ and won 55.8%, six tenths short. Both intervals run from about minus 3 to plus 2 and neither comes near excluding zero. The two-cent gap in what the sides cost is the settled lean already in the price. Buyers of the Under were buying the side that hits more often and paying more for it, in about the right proportion. There is no free Under on Polymarket and there is no Over tax. A bettor who takes every Under at 58¢ is paying 58¢ for a 58% chance and losing the spread and the fee. By sport the answer holds. The soccer Over is the closest thing to the folklore, minus 2.11 points and minus 7.5% on the dollar across 11,693 buys, and its interval runs from minus 6.5 to plus 2.4 because the buys cluster on a few big games. Baseball runs the other way, with Over buyers ahead and Under buyers behind, and the NBA's Over came in above zero. The sign of the Over's edge changed three times between April and July. Nothing in it says a side is systematically mispriced. ## Soccer totals: 1.5, 2.5 and 3.5 goals Most soccer totals are 2.5 goals, and the price of Over 2.5 is a compact statement of what the market thinks of the two teams. Over 2.5 buyers paid 54.6¢ and won 53.5% of the time; Under 2.5 buyers paid 54.2¢ and won 54.8%. Both on the price. At 1.5 goals, a line the market lists for games it expects to be tight, Over buyers paid 73.8¢ and won 71.3%. The line a bettor remembers is 3.5. Over 3.5 buyers paid 51.0¢ and won 46.1% of the time, minus 4.9 points and minus 20.8% on the dollar across 2,168 buys, and the interval runs from minus 16 to plus 7 over 415 markets. A bet that a game produces four goals was, in this window, wrong more often than its price said, and the sample cannot tell a mispricing from a low-scoring summer. Under 3.5 buyers, at 66.1¢, won 65.2%. The lesson for a soccer bettor is about the number rather than the side. The market prices 2.5 to the half point. It priced 4.5 and 5.5 Unders to the tenth. The one line where buyers were wrong by a margin was the one that asks for the most goals, and a bettor who can say why a game goes to four has a bet the crowd, this summer, could not price. ## Live totals A total keeps trading through the game, and the price moves with the clock as much as with the score. An Under gets more likely every minute nobody scores; an Over gets more likely with every goal and less likely with every scoreless minute. In-play Under buyers paid 64.5¢ on average and Over buyers 62.0¢, well above the pre-kickoff prices of 54¢, because by the time most live buys land the game has told the market something. The live prices were fair. In-play Over buyers won 62.0% at 62.0¢; in-play Under buyers won 64.7% at 64.5¢. Before kickoff both sides lost about a point to the price. The timing study at 0xinsider.com/research/when-large-sports-bets-land found the same on every market type: the in-play price was kinder to the buyer than the pre-game one. The lean toward the Under is a live phenomenon. Before kickoff the large buys split 52 to 48 for the Under; in-play they split 59 to 41. A live Under is a bet that the game stays as it is, and it is the side the money takes once the game has started. ## How the graded wallets bet totals 0xinsider grades every Polymarket wallet from S to F on its settled record, and from June 2026 each large buy carries the grade its wallet held that day. On game totals, wallets graded S, A or B put 60.5% of their buys on the Under. Wallets graded D or F put 50.7% on it. The profitable wallets lean the way the settled shares lean; the poorly graded wallets split the sides evenly. The graded cohort's Unders came in at plus 2.12 points and plus 8.15% on the dollar across 4,640 buys, with an interval from minus 2.8 to plus 6.9 that includes zero. Their Overs came in at minus 1.54 points. The poorly graded cohort lost on both sides, minus 4.10 points on Overs and minus 3.18 on Unders. That is the sharp money study's finding on totals, at 0xinsider.com/research/sharp-money-polymarket-sports, seen from the side of the bet. The fade study at 0xinsider.com/research/fading-the-crowd-polymarket-sports adds the other half: when the D and F wallets' money agreed on one side of a market before kickoff, the crowd lost most on totals, minus 4.85 points across 264 one-sided markets. A crowd on the Over of one game is the pattern to look for. The graded wallets' lean is a default, not a rule; its interval says so. ## How to bet a total on 0xinsider Each game on a 0xinsider sports board, 0xinsider.com/sports/soccer, 0xinsider.com/sports/mlb, 0xinsider.com/sports/nba, 0xinsider.com/sports/nfl, 0xinsider.com/sports/esports and the rest, lists its total beside the moneyline and the spread, with the Over and Under prices in cents. Write down the number of goals or points you expect before you read the price, because a total is a bet on your number against the market's, and the price is only good if yours is different. Open the total and its market page lists the wallets holding each side with the grade each has earned. Graded wallets on the Under with the poorly graded wallets on the Over is the study's pattern; both cohorts split is a fair price. The whale alerts feed at 0xinsider.com/whale-alerts shows each large buy as it lands with the buyer's grade, and a filter on the sport shows the totals buys among them. The guide at 0xinsider.com/learn/how-to-find-sharp-money-polymarket-sports walks through the surfaces in order. Then take the side whose price is below your probability, after the spread and the fee, and size it as the guide at 0xinsider.com/learn/how-to-use-kelly-criterion-prediction-markets describes. A total is the bet where the number is the whole argument. The data says the market prices the number well, the Under is the side that hits more often and costs more, and the edge, where there is one, is in knowing the game. ## Frequently Asked Questions What does over/under mean in sports betting? A bet on the combined score of a game against a number the market sets. Over wins if the game produces more than the number; Under wins if it produces less. Who wins the game does not matter. Does the under hit more often than the over? On Polymarket, yes: across 82,080 settled game totals from April 2 to September 13, 2026, the Under hit 52.7% of the time. Soccer went Under 54.3% of the time and esports 55.3%; baseball and hockey were coin flips; college football, the NBA and MMA totals went Over more often than not. Is betting the under profitable? Not by itself. Under buyers on Polymarket paid 58.4 cents on average and won 57.9% of their buys, half a point short of the price; Over buyers paid 56.4 cents and won 55.8%. The Under's higher hit rate is already in its higher price. Can an over/under bet push on Polymarket? No. Every one of the 80,848 settled game totals with a recorded line carried a half-point line, so each market settled Over or Under. Which side do sharp bettors take on totals? On Polymarket, wallets 0xinsider grades S, A or B placed 60.5% of their game-total buys on the Under from June 2026, against 50.7% for D and F wallets. Their Unders came in at plus 2.12 points with an interval that includes zero; the poorly graded wallets lost on both sides.