Betting Basics
Spreads
How point spreads work, why most are priced near -110, and why half points and key numbers matter.
By Jared Narz · · 2 min read
A point spread evens out a matchup by giving the underdog a head start. You're betting on the margin of victory, not just the winner.
How it works
- The favorite is listed with a minus: Team A -3. Team A must win by more than 3.
- The underdog gets a plus: Team B +3. Team B covers if it loses by less than 3 or wins outright.
- If Team A wins by exactly 3, it's a push and stakes are returned.
The price
Spreads are usually priced near -110 on both sides: risk $110 to win $100. That extra $10 is the sportsbook's margin. See Understanding Vig. Spreads can also be shaded, like -3 (-120) or +3 (-105).
Half points and key numbers
A half point (-3.5 or +2.5) removes the possibility of a push.
In football, games land on certain margins far more often than others, especially 3 and 7, because of how touchdowns and field goals score. Those are called key numbers. Moving across a key number (getting +3.5 instead of +2.5) is worth much more than moving between ordinary numbers, which is why books charge more for it.
Practical tips
- Compare spreads across books. +3.5 at one book and +3 at another are very different bets in football. See Why Line Shopping Matters.
- Know the key numbers in the sport you bet.
- Remember that a spread bet at -110 needs to win 52.38% of the time to break even.
Examples are illustrative and use hypothetical numbers. This article is educational content, not financial advice or a guarantee of results. 21+. Bet responsibly.