--- title: "How to Bet on MLB on Polymarket: Moneylines, Run Lines, Totals, NRFI and Player Props" canonical: "https://0xinsider.com/learn/how-to-bet-on-mlb-polymarket" datePublished: "2026-09-14" dateModified: "2026-09-14" description: "How Polymarket lists an MLB game, from the moneyline, run line and totals to NRFI, first-five-innings markets and player props, how each settles, where the money trades, and what the data says about home field and first innings." --- # How to Bet on MLB on Polymarket: Moneylines, Run Lines, Totals, NRFI and Player Props Last updated: 2026-09-14 Canonical: https://0xinsider.com/learn/how-to-bet-on-mlb-polymarket An MLB game on Polymarket carries a moneyline, a ladder of run lines and totals, a no-run-first-inning market and, on about half of 2026's games, first-five-innings markets and player props. This guide covers what each market is and how it settles (a hitter who does not play settles his props Under), where the money went on 2,229 games in 2026 ($1.79 billion, 71.3% of it on the moneyline), what the data says about home field (53.7%), one-run games (29.1%) and the first inning (no run in 49.4%), and how to follow the season on 0xinsider. ## An MLB game on Polymarket Polymarket lists each MLB game as an event titled with the away team first, "Texas Rangers vs. Arizona Diamondbacks" for the Rangers at the Diamondbacks. The moneyline pays $1 a share on the team that wins. Around it sit the run line, the total and smaller families of markets. Over the 2026 season to September 12, a game carried one moneyline, 7.1 total lines and 5.9 run line markets on average, plus a market on whether a run scores in the first inning. From June 10, about half the season's games also listed first-five-innings totals, winners and spreads, an extra-innings market, pitcher strikeout props and home run props, 31.4 home run markets a game. On September 2 Polymarket added hits, total bases, hits plus runs plus RBIs, outs recorded, walks, hits and earned runs allowed, and a winner market for each inning. On the 0xinsider event page for the Rangers and Diamondbacks on September 13, the Markets section counted $349K across six market families: $213K on the moneyline, $108K on the total and $26.3K on the run line. ## Where the money goes on an MLB game Across 2,229 MLB games from March 25 to September 12, 2026, Polymarket reported $1.79 billion in volume. The moneyline took 71.3% of it, totals 20.8% and the run line 7.0%. The first-inning markets took 0.6%, $10.6 million, and every other family together took less than half a percent. Read that as a map of liquidity. The 37,438 home run markets of the season traded $1.3 million between them, so a large order on a prop moves its price in a way the same order on a moneyline does not. Check a market's volume on its page before you size a bet. ## How MLB markets settle Each market's rules are on its page. The moneyline resolves to the team that wins. A postponed game keeps the market open until it is played, and a game canceled with no makeup, or one that ends in a tie, settles 50-50, so each share pays 50 cents. A run line such as "Spread: Chicago Cubs (-1.5)" resolves to the Cubs if they win by 2 or more runs and to their opponent otherwise. A total such as "O/U 10.5" resolves Over if the two teams combine for 11 or more runs. The first-inning market resolves Yes if either team scores in the 1st inning. First-five-innings markets settle on the score after the 5th inning: a tie there resolves the winner market to Draw and the spread to the team getting the runs. The extra-innings market resolves Yes once play begins in the 10th. Player props have their own rules, and they differ by role. A hitter prop, such as home runs, hits or total bases, counts the whole game including extra innings, and resolves Under if the hitter does not take the field. A pitcher prop, such as strikeouts, outs recorded or earned runs allowed, resolves 50-50 if the named pitcher does not start, and on his final total if he starts and leaves early. Check the lineup before you buy a hitter's Over. ## Reading an MLB price A Polymarket share pays $1, so its price is a probability. A team at 58¢ is a 58% chance to win, and the other team trades near 42¢. Buy $100 of the 58¢ side and you hold about 172 shares that pay about $172 if the team wins. Sportsbook odds convert the same way. A favorite at -138 is 138 divided by 238, 58%; an underdog at +138 is 100 divided by 238, 42%. The chart below draws that conversion across the range. A sportsbook's two sides add up to more than 100%, while the two sides of a Polymarket market add up to about $1, and the cost of trading is the spread and, on a taker order, Polymarket's fee. ## What home field is worth in MLB MLB home teams won 53.7% of 4,521 regular-season and postseason games settled on Polymarket, nearly all from the 2025 and 2026 seasons, with a half-width of 1.45 points: 54.1% in 2025 and 53.2% in 2026. That ties the NFL for the smallest home edge of the five US pro leagues in the study at 0xinsider.com/research/home-field-advantage-polymarket, and with eight times the NFL's sample it is the better-measured of the two. The price already carries it. Large Polymarket bets on MLB home sides and away sides each came in within about a third of a point of what they paid, so a home team is not a bet in itself. ## The run line and one-run games The run line is baseball's spread, and its standard number is 1.5 runs. A favorite at -1.5 has to win by two; an underdog at +1.5 wins the bet by winning the game or losing by one. Polymarket lists more than one line for most games, for both teams, so the Rangers and Diamondbacks game on September 13 listed the Rangers from -1.5 to -5.5 and the Diamondbacks at -1.5 and -2.5. One-run games decide the run line. 29.1% of 1,882 MLB games settled on Polymarket were decided by exactly one run, with a half-width of 2.05 points. In a one-run game every +1.5 bet wins and every -1.5 bet loses, whichever team won. The chart below shows the rate month by month. The guide at 0xinsider.com/learn/point-spread-betting-explained covers spreads across sports. ## Totals in MLB An MLB total is a ladder of lines, each paying Over or Under on the combined runs. Of 14,519 baseball total lines that settled from April 2 to September 13, 2026, 49.8% went Under, with a half-width of 0.81 points, so neither side of a baseball total has settled more often than the other. Large buyers of MLB Overs paid 51.7¢ and won 52.7% of the time over 4,834 buys; buyers of Unders paid 52.8¢ and won 50.5% over 5,104. Both intervals include zero. The guide at 0xinsider.com/learn/over-under-betting-explained covers how totals are priced. ## NRFI and first-inning bets NRFI means no run first inning: the No side of Polymarket's first-inning market, and Yes is YRFI. No run scored in the first inning of 49.4% of 2,237 MLB games with a settled market from September 2025 to September 12, 2026. The home team scored in the bottom of the first in 32.7% of games and the away team in the top in 26.4%, as the chart below shows. At first pitch the no-run side cost 51.4 cents on average, about two points more than it hit. $1 on NRFI in every game lost 6.38% after Polymarket's sports taker fee, an interval that excludes zero, while $1 on YRFI returned plus 2.28%, inside the noise. Team NRFI records spread no wider than chance would produce. The study is at 0xinsider.com/research/nrfi-polymarket. Before April 2, 2026 the market was titled "NRFI: vs. " and Yes paid when no run scored. Read a market's rules before you read its price. ## First five innings, extra innings and inning markets A first-five-innings market settles after the 5th inning, so the late innings are out of the bet. The winner market is three-way, one market per team and one for a tie, because a game can be level after five. The total and spread work like their full-game versions on five innings of runs. The extra-innings market pays Yes if the game reaches the 10th inning. The inning winner markets, listed from September 2, pay on which team scores more runs in one inning, with a Draw when neither scores more. These families trade thinly, so check each market's volume before you trade it. ## Live MLB betting MLB markets keep trading after first pitch, and the prices move with every run. Across sports, 48.6% of large Polymarket buys in the April to September 2026 timing study landed after the start, and in-play prices were fairer to the buyer than prices days before the game; the study is at 0xinsider.com/research/when-large-sports-bets-land. A limit order at your price avoids chasing a moving market, and a resting order that fills pays no taker fee. To take a position off during the game, sell your shares; the guide at 0xinsider.com/learn/cash-out-betting-explained covers when that makes sense. ## How to follow MLB on 0xinsider The MLB board at 0xinsider.com/sports/mlb lists live and upcoming games with an active Polymarket market. Each card shows both teams' prices and chances, the price move over the last hour and the last 24 hours, the inning and score for a live game, the most traded prop market, and the top five holders on each side with their grades and baseball win rates. Open a game for its event page. The Markets section lists every market family with a line ranking where the money is. The whale alerts feed at 0xinsider.com/whale-alerts shows every large trade as it fills, marked BUY or SELL, with the wallet's grade, and the guide at 0xinsider.com/learn/how-to-find-sharp-money-polymarket-sports walks through reading that record for one game. ## Frequently Asked Questions Can you bet on MLB on Polymarket? Yes. Polymarket lists MLB games with a moneyline, run lines, totals and a first-inning run market, and on many games first-five-innings markets, an extra-innings market and player props. Each market pays $1 a share on its outcome, and the price is the market's probability. What happens to a Polymarket MLB bet if the game is postponed? The market stays open until the game is played and settles on that game. A game canceled with no makeup settles 50-50, and so does a moneyline on a game that ends in a tie. What does NRFI mean? No run first inning: a bet that neither team scores in the 1st inning. On Polymarket it is the No side of "Will there be a run scored in the first inning?", and no run scored in 49.4% of 2,237 settled games. What happens to an MLB player prop if the player does not play? A hitter prop resolves Under if the hitter does not take the field. A pitcher prop resolves 50-50 if the named pitcher does not start. How often do MLB home teams win? 53.7% of 4,521 MLB regular-season and postseason games settled on Polymarket, nearly all in the 2025 and 2026 seasons: 54.1% in 2025 and 53.2% in 2026.