Why NBA Home Court Advantage Is Disappearing

By Justin Pietsch · August 7, 2026

The whole case in brief; the eight-part series behind it starts with Home Court Advantage Is Fading.

For as long as we can measure, the NBA has had a home court advantage. Across that record, the home edge has shrunk, though the regular season and playoffs have followed different paths. In the mid-1980s, the home team won about 65% of NBA regular-season games. Today it wins about 55%. The playoffs fell just as far, from about 68% to 58%.

There are lots of guesses about why home court advantage is falling, some of them are correct, but some of the reasons for the falling are surprising. It’s probably not all the reasons you’d expect. If this was a mystery, there would be some obvious suspects and some new suspects as we go along. Some of the suspects aren’t guilty.

Spoiler alert: The biggest changes show up in how the game is played. The move to the three-point line accounts for close to half the decline, through shooting, fouls, and turnovers. The home team’s edge in foul calls mostly disappeared. Home teams also lost almost all of their old advantage on the offensive glass.

Also spoiler: it wasn’t better travel, or more rest or some of the other obvious suspects.

Since I gave away the answer, why read this? You learn about what home court advantage is made up of and how that has changed. And all the different possible suspects we had that turned out to have no impact. You might want evidence I did this thoroughly, or how I came to these conclusions.

Has home court advantage really shrunk? What caused it to shrink? And what didn’t?

1. Yes, Home Court Advantage Really Shrank

It happened everywhere. Every franchise with a long enough record saw its home edge shrink. Denver and Utah still hold the biggest home edges in the league, though their edges have faded too. The advantage hasn’t vanished, since home teams still win clearly more than half their games. But in the tight games, the ones decided by a basket or two, the home team now wins about half.

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.

In a separate comparison of favorites and underdogs, the gap between their home win rates narrowed in the last four postseasons, mostly because favorites won less often at home. The full-record playoff decline persists when the teams’ quality gap is removed. A best-of-seven series dilutes the edge that remains: run today’s regular-season home edge through a simulated series between two equal teams, and the one with home court wins about 52% of the time, barely better than a coin flip. The full story of the decline: Home Court Advantage Is Fading. The postseason: The Playoffs Are Different (and the Same).

2. What Took It Away

Home advantage showed up in familiar parts of the game. Home teams shot better, rebounded more, turned the ball over less, and got more help from the whistle. Those are the four factors: shooting, rebounding, turnovers, and fouls, with foul calls standing in for free throws. Together they account for about 95% of the advantage. The shot chart changed, the foul edge shrank, and the rebounding edge nearly vanished.

The game moved to the arc

Threes grew from about 7% of shots in the mid-1980s to about 40% today while home court advantage faded. Those two things in parallel alone do not show that more threes caused the decline. Among games from the same period, those with more threes had a lower home win rate than those with fewer. That means a smaller home edge, not home teams turning into underdogs. When games are compared at similar three-point rates, the home shooting edge no longer declines over time. The rise in threes also accounts for about half of the fading foul and turnover edges, plausibly because fewer shots start as drives to the basket. Across shooting, fouls, and turnovers together, the rise in threes accounts for close to half the decline in home court advantage.

The friendly whistle faded

The home whistle advantage was real and nearly universal: of the 47 officials with at least 50 playoff games on record, 45 called fewer fouls on the home team. In the regular season, home teams once shot about 2 more free throws a game than visitors. Today the gap is about 0.5.

Two extra free throws a night sounds too small to matter, and on most nights it is. Most games aren’t close, so the edge only has to tip the minority that are, and that is enough to bend a season’s win rate. Each change has its own article: The Whistle and The Three-Point Suspect.

The glass and the turnover gap

The biggest unanswered part of this story is rebounding. In the mid-1980s, home teams grabbed about 34% of their own misses, against 31% for visitors. Today both are near 26%. Offensive rebounding fell for everyone, but farther at home; the home edge nearly vanished, and the rise in threes explains almost none of that loss.

Why the home rebounding edge vanished remains open. The home turnover edge also nearly disappeared; the rise in threes accounts for about half that loss, but the data do not explain why visiting teams closed the rest of the gap. Teams may have sent fewer players to crash the glass; on turnovers, better scouting may have helped visitors prepare. The data can’t confirm either one. The two open questions are in The Glass and the Turnover Gap.

The scorecard

So which mattered more, rebounding or threes? The table shows where the home edge disappeared: rebounding is the largest single piece. The move to the arc is the largest explanation this analysis can trace, but it gets no row because it works through shooting, fouls, and turnovers. One tells us where the advantage faded; the other helps explain why.

These are regular-season shares, and the shares in both columns shift a bit depending on which games are counted, and rebounding’s lead over turnovers is narrow. The playoffs point the same way on far fewer games, but there the four factors account for only about 67% of the decline.

3. What Didn’t Do It

If home court advantage were about crowds, emptier arenas might be an early suspect. They aren’t empty. Outside the 2020–21 pandemic season, attendance stayed within about a tenth of record levels in every one of the 27 years with attendance figures, and the recent seasons, when home court advantage was at its lowest, were among the fullest.

The one season the fans really did disappear is the obvious place to look again. In 2020–21, home teams won about 51% in empty arenas, barely better than a coin flip, and about 59% where fans were let in. Fans may help, but those games differed in other ways too, and among games with fans, the data detect no link between crowd size and home wins.

The other usual suspects come up short as well.

Every ruled-out suspect in full: The Usual Suspects.

Appendix A: Companion Documents

Data: NBA.com Stats, pulled with the open-source nba_api tool; attendance records from Basketball-Reference.