The point spread is the most popular bet type in American sports betting. If you watch football or basketball, you’ve seen lines like “Chiefs -3.5” or “Celtics -6.” Here’s exactly what those numbers mean and how to bet them.
What is a Point Spread?
A point spread is a number set by the sportsbook that represents the expected margin of victory. It levels the playing field so that both sides of a bet are roughly equally attractive, regardless of how lopsided the matchup is.
| Team | Spread | Odds |
|---|---|---|
| 49ers | -6.5 | -110 |
| Cardinals | +6.5 | -110 |
The favorite (49ers) has a negative spread (-6.5). They need to win by 7 or more points for a bet on them to cash.
The underdog (Cardinals) has a positive spread (+6.5). They can lose by up to 6 points and a bet on them still wins.
Think of it as a head start. The Cardinals are starting the game with a virtual 6.5-point lead. After the real score is determined, you add 6.5 to the Cardinals’ score (or subtract 6.5 from the 49ers’ score) and see who “wins.”
How to Read Spread Bets
The Number
The spread itself (e.g., -6.5 or +6.5) tells you the margin. Half points (.5) exist to prevent pushes — one side always wins.
Whole numbers (like -3 or -7) can result in a push — a tie against the spread. If the Chiefs are -3 and win by exactly 3, every spread bet is refunded.
The Odds
The odds next to the spread (usually -110) tell you what you pay. At -110, you bet $110 to win $100. Both sides are typically priced around -110, though the odds can shift based on betting action.
When a sportsbook adjusts the spread, they might also move the odds instead:
| Scenario | Spread | Odds |
|---|---|---|
| Standard | Chiefs -3 | -110 |
| More action on Chiefs | Chiefs -3 | -115 |
| Even more action | Chiefs -3.5 | -110 |
Books can move the line, the odds, or both to balance their risk.
Spread Betting in Different Sports
Football (NFL and College)
Football spreads are the most heavily bet market in America. Common features:
Key numbers: 3 and 7 are the most important numbers because touchdowns (7) and field goals (3) are the most common scoring plays. About 15% of NFL games are decided by exactly 3 points.
Typical range: NFL spreads rarely exceed 14 points. College football spreads can be 30+ points.
Half point matters: The difference between -3 and -3.5 is enormous in football because so many games land on exactly 3.
Basketball (NBA and College)
Basketball spreads tend to be larger and less “sticky” around key numbers because scoring is more continuous:
Typical range: NBA spreads can be anywhere from 1 to 15+ points.
More variance: Basketball has runs and comebacks that make spreads less predictable than football.
Totals often more popular: Many sharp bettors prefer NBA totals over spreads because they’re more modelable.
Other Sports
Baseball: Uses a “run line” (typically -1.5 / +1.5) instead of a traditional spread. The favorite must win by 2+ runs.
Hockey: Uses a “puck line” (typically -1.5 / +1.5). Same concept — the favorite must win by 2+ goals.
Soccer: Uses goal lines that work like spreads (e.g., -0.5, -1.5).
Key Numbers in Football
Not all spreads are equal. In the NFL, certain margins of victory happen far more often than others:
| Margin | NFL Frequency |
|---|---|
| 3 | ~15% |
| 7 | ~9% |
| 6 | ~5% |
| 10 | ~4% |
| 1 | ~4.5% |
| 4 | ~4% |
| 14 | ~3.5% |
The numbers 3 and 7 account for about 24% of all NFL outcomes. This is why the spread moving from -2.5 to -3.5 (crossing through 3) is one of the most significant moves in football betting.
What Moves the Spread?
Spreads move for several reasons:
Betting action
When more money comes in on one side, the book moves the line to balance risk. Heavy Chiefs -3 action might push the line to Chiefs -3.5.
Sharp money
When professional bettors (sharps) bet one side, books often move quickly — even if the dollar amount is small. Sharps are respected because they have winning track records.
Injuries and news
A starting quarterback being ruled out can move a spread 3-5 points. Weather, suspensions, and coaching changes all factor in.
Public perception
Popular teams (Cowboys, Lakers, Yankees) tend to attract more public money, which can inflate the spread beyond what the matchup warrants. This sometimes creates value on the other side.
Spread Betting Strategy
Look at the number, not just the team
Asking “will the Chiefs win?” is a moneyline question. Asking “will the Chiefs win by more than 3.5?” is the spread question. A team can dominate and still not cover the spread, or lose the game outright and cover easily.
Key number awareness
In football, getting +3 instead of +2.5 or -6.5 instead of -7 is a big deal. Those half points across key numbers are worth paying attention to. In basketball, key numbers matter less because the scoring is more granular.
Compare across books
The spread on the same game can differ by half a point or more across sportsbooks. Getting +3.5 instead of +3 at no extra cost is free value. Always compare across books before placing a spread bet.
Try the half-point-calculator→
Common Beginner Mistakes
Confusing the spread with the moneyline
“Cowboys -7” means they need to win by 8+, not that they’re expected to win. New bettors sometimes think a team covers the spread just by winning the game.
Ignoring the odds
Two books might both have Chiefs -3, but one at -110 and another at -105. That 5-cent difference in vig adds up over hundreds of bets.
Chasing big spreads
Betting on 14-point underdogs because “anything can happen” is a common trap. Yes, upsets happen, but massive underdogs that cover are rarer than they feel.
Key Takeaways
The point spread represents the expected margin of victory — favorites have negative spreads, underdogs have positive
At -110 odds, you need to win 52.4% of spread bets to break even
In football, 3 and 7 are the most important key numbers — games land on these margins far more often than others
Spreads move based on betting action, sharp money, injuries, and public perception
Always compare spreads across multiple sportsbooks — a half point can make the difference between a win and a loss
