Kansas City Royals @ Houston Astros
Tue Sep 15, 8:10 PM ET
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Odds from the latest scan: September 14, 3:42 PM ET. Live odds for this game.
Polymarket US pays the most on Kansas City Royals at +138, and BetOnline pays the most on Houston Astros at -145. Across the 10 books pricing this game the best and worst numbers are $8.00 apart on a $100 bet.
Best MLB price on Kansas City Royals vs Houston Astros, compared across every major US sportsbook plus Kalshi, Polymarket US, ProphetX and Novig. Tue Sep 15, 8:10 PM ET.
Games starting within 24 hours refresh every minute; later games every 30 minutes and every hour as kickoff approaches during the beta; the free board refreshes hourly.
Moneyline Line HistoryKansas City Royals +138 Polymarket US·Houston Astros -145 BetOnline
Every Book's Moneyline
| Book | Kansas City Royals | Houston Astros |
|---|---|---|
| BetOnline | +131 | -145 |
| LowVig | +131 | -145 |
| Caesars | +130 | -155 |
| Fanatics | +130 | -155 |
| theScore Bet | +135 | -155 |
| Polymarket US | +138 | -159 |
| BetMGM | +135 | -160 |
| Kalshi | +134 | -160 |
| DraftKings | +133 | -161 |
| FanDuel | +136 | -162 |
Spread Line HistoryKansas City Royals +1.5 (-135) Fanatics·Houston Astros -1.5 (+135) theScore Bet
Total Line HistoryOver 8 (-102) LowVig·Under 8 (-113) LowVig
About These Charts
Player Props
10 books priced this game. Prediction market prices include trading fees wherever a fee applies, so they are directly comparable to sportsbook lines.
On Kansas City Royals vs Houston Astros, the best available price is not the same at every book. One sportsbook might post a side at -110 while another has it at -102, and taking the better number is the one edge you fully control. The Odds Gap scans every major US sportsbook plus the federally regulated prediction markets and flags where the best price sits on each side of this MLB matchup.
How to read these Kansas City Royals vs Houston Astros odds
The cards above show the best moneyline price on each side and which book has it. The spread line shows Houston Astros at the market's consensus number, priced at the best odds among books quoting it. The total shows the Over at the consensus number. For every book's price on every market, open the game in the Line Shop.
What the Price Gap Is Worth
Across the 10 books quoting this side, the best price is +138 at Polymarket US and the worst is +130 at Caesars. Same bet, same outcome, $8.00 difference in profit on a $100 stake. Nothing about the wager changes, only where you place it.
- Kansas City Royals: best +138 (Polymarket US), worst +130 (Caesars)
- Houston Astros: best -145 (BetOnline), worst -162 (FanDuel)
Where This Line Opened
We capture the opening number once from the historical archive, so this is the price that was actually posted at BetOnline, not a reconstruction. Nobody had this game priced before it.
- Houston Astros: BOL open -145, now -145
- Kansas City Royals: BOL open +131, now +138 (7 cents longer)
The charts above plot every scan since, so you can see whether the move came in one step or drifted.
Kansas City Royals vs Houston Astros Odds: Common Questions
Who has the best odds on Kansas City Royals vs Houston Astros?
At the latest scan Polymarket US pays the most on Kansas City Royals at +138, and BetOnline pays the most on Houston Astros at -145. Those are two different books more often than not, and the best number moves as books reprice, so check the table on this page before you bet rather than assuming one book wins both sides.
How much does the price differ between sportsbooks on this game?
Right now 10 books price this side, and the spread between the best and worst of them is +138 at Polymarket US versus +130 at Caesars. On a $100 bet that is $8.00 more in your pocket for the same wager, won or lost the same way. That difference is the entire reason this page exists.
Where did the Kansas City Royals vs Houston Astros line open?
Houston Astros opened -145 at BetOnline and is -145 now. We capture the opener once from the historical archive rather than inferring it, so the number on this page is the price that was actually posted, and the movement charts above plot every scan since.
What is the spread and total for Kansas City Royals vs Houston Astros?
The consensus spread is -1.5 on Houston Astros with the best juice at +135 (theScore Bet), and the consensus total is 8 with the best Over price at -102 (LowVig). Consensus means the line most books agree on; the flagged price is the best juice available at that same number.
How often do these MLB odds update?
The free board rescans every hour from 7am to 1am ET; Live Beta, free with an email signup during the beta, refreshes every minute. This page was last scanned September 14, 3:42 PM ET, and that timestamp is shown above the table.
Does The Odds Gap pick a side on Kansas City Royals vs Houston Astros?
No. There is no model, no projection, and no lean anywhere on this site. We show which book pays the most on a bet you have already decided to make. Math, not picks.
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