Straight answers to the questions readers ask most about the NBA’s fading home court advantage. The full story is the eight-part series, and why home court advantage is disappearing answers the big questions in one place.
Every answer below is pulled from the same public NBA game logs behind the rest of the series, and points you to the article that covers it in full.
The short version
Has home court advantage really shrunk?
Yes. In the regular season the home team’s win rate fell from about 65% to 55%, and in the playoffs from about 68% to 58%, a drop of roughly 10 percentage points in both. In the regular season, the scoring gap followed: the home team’s edge in points per 100 possessions is down by more than a third since the mid-2010s.
Is this a regular-season story or a playoff story?
Both. Each fell by roughly 10 percentage points. The playoff home win rate averaged about 68% in 1984–94, then about 64% in each period from the mid-1990s through 2017. The later periods were lower again: about 61% in 2018–22 and 58% in 2023–26. The smaller postseason sample cannot reliably identify a turning year. With about a fifteenth as many games, the playoff numbers show the direction more reliably than the exact size. The Playoffs Are Different (and the Same) covers the playoff side, including how the favorite’s home edge has changed lately.
Does playing at home still matter?
Yes. Home teams still win clearly more than half their regular-season games, so the advantage has not vanished; it is just worth far less than it was. Empty-arena games in the 2020–21 regular season offer a clue about crowds: home teams won about 51%, a hair above a coin flip.
What’s behind the decline
You call both rebounding and the three-point boom the biggest factor, so which is it?
Both, because they answer two different questions, and running them together is the most confusing part of this story. The first question is where the decline shows up among the four factors: shooting, rebounding, turnovers, and fouls, with foul calls standing in for free throws. In the regular season the answer is rebounding, the largest share of the decline, with the turnover edge close behind; in the playoffs rebounding still leads, but on far fewer games neither share is pinned down. The second question is which change in how the game is played explains the most of the decline. There the answer is the rise in threes, the larger of the two causes the data can trace (the other is the officiating change), accounting for close to half the decline. The two answers don’t compete, because the rise in threes works through shooting, fouls, and turnovers, not rebounding. So rebounding is at once the largest factor in the decline and a change this analysis cannot explain.
Did the three-point boom kill home court advantage?
It explains more of the decline than any other cause the data can trace, but it works through three of the four factors rather than being the whole story. The share of shots taken from deep has climbed to about 40%. Compare games at the same three-point rate, and the decline in the home shooting edge disappears entirely; the rise in threes also accounts for about half of the fading foul and turnover edges, close to half the decline in all. What it doesn’t explain is rebounding, the largest factor, which is why it covers a lot of the decline but not all of it. The Three-Point Suspect asks how much it really explains.
Are the referees really biased toward the home team?
They were, in every decade, and in the regular season the gap has mostly closed. Of the 47 officials with at least 50 playoff games on record, 45 called fewer fouls on the home team. In the regular season the home foul edge has shrunk about 80%, and the extra free throws home teams once drew have nearly disappeared. The Whistle covers the foul calls.
If rebounding is the biggest factor, why can’t you explain it?
The game logs show exactly what happened but not why. The home team’s offensive-rebound rate fell about 8 points while the visitor’s fell about 5, so the home edge on the glass collapsed to almost nothing. The box score can’t say what changed on the court: less crashing, better defensive positioning, or something else. The Glass and the Turnover Gap opens that case.
What is not behind it
Is it because crowds got smaller?
No. Outside the 2020–21 pandemic season, crowds stayed within about a tenth of record levels in every season with attendance figures, and the recent seasons, when home court advantage was at its lowest, were among the fullest. In the 2020–21 regular season, home teams won about 51% in empty buildings and 58.6% with fans present. That gap suggests crowd presence may help, though the games were not randomly assigned; among games with fans, the data detect no further link between crowd size and home wins.
Was it better travel, more rest, or load management?
Mostly no. Travel distance and time zones are too small to bend a 40-year trend, and rest matters on a given night but its edge hasn’t shrunk over the decades. Fewer back-to-backs for tired visitors explain only about 8% of the regular-season decline.
Is it just that teams are more evenly matched now?
No, not over the long run. Seasons with more parity had slightly bigger home edges, but the decades-long slide is there in balanced and lopsided seasons alike. More even matchups can’t bend a 40-year trend.
Did the 2014 playoff format change cause the playoff drop?
Not detectably. The playoff home rate did fall after 2014, but once the long-run decline is allowed for, the format adds no clear step of its own, though the playoff games are too few to pin down exactly when the drop began. The Usual Suspects tests this alongside the other suspects.
The playoffs and the practical stuff
Should I still expect the home team to win a playoff series?
Barely, once you take the better team out of it. Playing at home still shows up game by game: the host, always the higher seed in Game 1, wins about 74% of Game 1s and still takes about 72% of Game 7s, so road teams show no sign of adjusting as a series wears on. But the series format dilutes that edge. Run the regular-season per-game rate through a simulated series between two otherwise evenly matched teams, and the home-court team, which took the series about 55% of the time in the 1980s, now wins it only about 52%. The playoffs’ own series odds come out a shade higher, at about 53%, though the two are not far enough apart to separate on the playoff games available, and both are barely better than a coin flip. A real playoff series pits a higher seed, usually also the better team, against a lower one, so an actual home-court favorite wins more often than these figures alone suggest. The Playoffs Are Different (and the Same) covers it.
Which arenas are still the hardest to play in?
Denver and Utah. After allowing for the random bounce of a short schedule, Denver holds a home-road gap of about 26.8 percentage points across its whole record and Utah about 25.6, well above the league average of about 20 points among qualifying franchises. Thin mountain air is the most plausible reason, though with only two altitude teams it can’t be fully separated from whatever else those two franchises have in common. Split the record at 2002 and Denver’s edge is down about 13 points from the first half to the second, yet since 2002 the two still hold the league’s largest home edges. That is the regular season; in the playoffs there are too few games per building to tell arenas apart at all. The Altitude Exception takes a closer look.
Will home court advantage keep shrinking until it’s gone?
The data can’t tell us whether it will vanish entirely. The trend line points further down, from about 54.9% today toward about 53.5% by 2031 in the regular season, with the playoffs pointing the same way, though the range around that path is wide enough to include today’s level. The 2020–21 regular-season games played to empty buildings are the closest thing we have to a floor, at about 51%, though half a season of empty arenas doesn’t settle where the bottom is.
Can I trust this?
How do you know this isn’t cherry-picked or just noise?
Every number here comes from the official NBA game logs for more than 52,000 regular-season and playoff games since 1983–84, public data on NBA.com that anyone can download, plus attendance records from Basketball-Reference. Each headline claim was run through checks built to break it. The full battery is its own article, How I Know This Isn’t Made Up, and the tests behind each finding are laid out in the investigation.
Start the series: The Disappearing Home-Court Advantage. Or read why home court advantage is disappearing: the big questions in one place.
Data: NBA.com Stats, pulled with the open-source nba_api tool; attendance records from Basketball-Reference.