How Often Are NBA Games Blowouts? Margin of Victory Data
Blowouts and nail-biters turn up almost equally often in the NBA, but the blowout share has climbed sharply and the closing spread tells you which one to expect.
Every time I price an alternative spread or a winning-margin market, I want to know how often an NBA game actually turns into a rout, and how often it comes down to the final possession. So I went through 32,190 games, covering regular season, play-in and playoffs, to find the real shape of NBA margins.
The headline is a near tie. 15.7% of games were decided by 20 or more points and 15.3% by 3 or fewer, so blowouts and coin-flips arrive at much the same rate. That balance has not held steady, though. The recent seasons have tipped heavily towards lopsided finishes, and the spread separates the two outcomes more cleanly than most bettors assume. This study sits behind the margin thinking on my NBA predictions page.
1Most NBA games land between four and fourteen
Start with the full distribution. The median winning margin was 9 points and the average 11.3, and 48.7% of games were decided by double digits. In practice that makes a ten-point game about as likely as not, which is a far more useful anchor than any highlight reel.
The tail is where the pain sits. Games decided by 20-29 points made up 11.8% of the total and games decided by 30 or more 3.9%. Those two highlighted bars are what wipe out an alternative spread on the underdog and pay out a big-margin ticket on the favourite.
View the data: how nba games are decided: final margin
| All 32,190 games, 2001-02 to 2025-26 | |
|---|---|
| 1-3 points | 15.3% |
| 4-6 points | 18.0% |
| 7-9 points | 18.0% |
| 10-14 points | 20.5% |
| 15-19 points | 12.5% |
| 20-29 points | 11.8% |
| 30+ points | 3.9% |
The gap between the median and the average tells its own story. A long right tail of routs pulls the mean above the typical game, so I build margin expectations from the median, not the average.
2Seven points is the single most common final margin
Look at individual margins and the most common result is 7 points, from 2,034 games or 6.3%. Right behind it come 5 points and 6 points at 6.2% each, with 8 points on 6.0%.
Notice that 3 points, at 5.7%, does not top the table the way it would in American football. Basketball scores in small, frequent steps, and late intentional fouling stretches close games out to two or three possessions instead of holding them on a single key number.
| Margin | Games | Share |
|---|---|---|
| 7 points | 2,034 | 6.3% |
| 5 points | 2,011 | 6.2% |
| 6 points | 1,989 | 6.2% |
| 8 points | 1,946 | 6.0% |
| 3 points | 1,847 | 5.7% |
| 9 points | 1,803 | 5.6% |
| 4 points | 1,802 | 5.6% |
| 2 points | 1,763 | 5.5% |
For me that means no single NBA margin carries enough weight to justify paying heavily for a half-point, but the band from 5 to 8 points is where buying or selling a line matters most.
3Twenty-point blowouts have surged in the recent era
This chart is the reason I wrote the study. The share of 20-point blowouts was lowest at 12.0% in 2004-05 and peaked at 22.8% in 2025-26. In 2001-02 the figures were 13.3% for blowouts and 17.0% for games decided by 3 or fewer. In 2025-26 they were 22.8% and 14.0%.
So the near tie in the all-time numbers hides a crossover. Close games have drifted only slightly lower, but the blowout line has climbed steeply. I put that down to higher pace and heavier three-point volume, because a cold or hot shooting run now produces much bigger swings.
View the data: blowouts and close games by season
| Won by 20+ | Won by 1-3 | |
|---|---|---|
| 2001-02 | 13.3% | 17.0% |
| 2002-03 | 14.6% | 17.0% |
| 2003-04 | 12.7% | 15.7% |
| 2004-05 | 12.0% | 18.0% |
| 2005-06 | 12.4% | 17.4% |
| 2006-07 | 13.4% | 17.4% |
| 2007-08 | 16.8% | 13.8% |
| 2008-09 | 14.6% | 14.5% |
| 2009-10 | 14.1% | 13.9% |
| 2010-11 | 12.1% | 15.1% |
| 2011-12 | 14.5% | 16.9% |
| 2012-13 | 15.0% | 15.4% |
| 2013-14 | 14.5% | 15.7% |
| 2014-15 | 14.3% | 14.2% |
| 2015-16 | 15.1% | 14.2% |
| 2016-17 | 16.2% | 14.7% |
| 2017-18 | 14.0% | 14.9% |
| 2018-19 | 18.6% | 15.2% |
| 2019-20 | 16.5% | 15.2% |
| 2020-21 | 19.0% | 14.3% |
| 2021-22 | 19.3% | 13.6% |
| 2022-23 | 15.6% | 15.4% |
| 2023-24 | 19.6% | 14.0% |
| 2024-25 | 21.1% | 15.4% |
| 2025-26 | 22.8% | 14.0% |
One caveat runs through all of this. The 2011-12 and the shortened 2019-20 and 2020-21 seasons are smaller samples, and every band here describes past outcomes, not a forecast for any single game.
4The closing spread reshapes how lopsided games get
Spreads cover 2017-18 to 2025-26. With a closing spread of 14 points or more, 39.7% of games ended in a 20-point margin, from 494 games, and the favourite itself won by 20 or more 39.1% of the time. At 10 to 13.5, the favourite won by 20 or more 24.6% of the time.
The surprise sits at the other end. In games priced from pick to 2.5, 28.6% were decided by 5 points or fewer, yet 15.5% still ended as 20-point blowouts. A tight line does not promise a tight game. With a spread of 6 to 9.5, 25.3% of games were decided by 5 or fewer and 19.3% by 20 or more.
View the data: final margin by closing spread
| 5 or fewer | 6-19 | 20 or more | |
|---|---|---|---|
| Pick to 2.5 (2,398) | 28.6% | 55.8% | 15.5% |
| 3 to 5.5 (3,555) | 29.4% | 56.9% | 13.7% |
| 6 to 9.5 (3,477) | 25.3% | 55.4% | 19.3% |
| 10 to 13.5 (1,615) | 19.9% | 54.6% | 25.6% |
| 14 or more (494) | 10.5% | 49.8% | 39.7% |
Playoff games were decided by 20 or more points 17.6% of the time, against 15.6% in the regular season, so the postseason does not shrink margins either.
Betting notes
- Anchor on the median. The median winning margin was 9 points against an average of 11.3, so set your margin expectations from the typical game and treat the rout tail as a separate risk.
- Respect the big spreads. With a closing spread of 14 or more, the favourite won by 20 or more 39.1% of the time. Weigh that before taking the underdog on an inflated alternative line.
- Distrust tight lines. Pick to 2.5 games still produced 15.5% blowouts, so avoid stacking close-finish legs in a parlay on the strength of a short spread.
Quick answers
How often is an NBA game a blowout?
Across 32,190 games, 15.7% were decided by 20 or more points. That figure reached 22.8% in 2025-26, the highest season in the data.
What is the most common margin of victory in the NBA?
Seven points, which covered 2,034 games or 6.3% of the total. Five and six points follow at 6.2% each.
Are close NBA games more common than blowouts?
Over the full period they are nearly level, with 15.3% decided by 3 or fewer against 15.7% by 20 or more. In 2025-26, blowouts at 22.8% clearly outnumbered close games at 14.0%.
I'm Eleanor Whitfield, based in London, and I run the NBA picks and parlays at bettips.vip โ leaning on pace, efficiency and matchups over gut and reputation.
All of Eleanor Whitfield's work โ
