How the run line works
Because most baseball games are decided by a run or two, books use a fixed 1.5-run spread instead of a variable number. Taking a -1.5 favorite gets you a better price than the moneyline but requires a two-run win. Taking a +1.5 underdog costs more than the moneyline but gives you a cushion: you win if your team wins or loses by one.
A worked example
A favorite is -180 on the moneyline but +130 on the run line at -1.5. If they win 5-2, they cover -1.5 and the run line pays +130, more than the moneyline would. If they win 3-2, the moneyline cashes but the run line loses. That is the trade: a bigger payout for the extra run of risk.
When to use the run line
The run line rewards you for backing strong favorites expected to win comfortably, and it lowers the cost of backing live underdogs. Run-line splits often diverge from the moneyline on the same game, so check where the money sits in each market before you decide which one gives you the better number.
Frequently asked questions
Is the run line always 1.5?
Almost always. Standard MLB run lines are set at 1.5 runs. Some books offer alternate run lines at 2.5 or higher for different prices.
What does -1.5 mean on the run line?
The favorite must win by two or more runs for the bet to cover. A one-run win does not cover -1.5.
Related terms
21+. For entertainment and educational purposes, not financial advice. If gambling stops being fun, take a break. 1-800-GAMBLER. Regulated US books only.