It's almost 50/50 now and has been getting closer in the last 6 seasons.
How often does the home team win in the NFL?
On average, NFL home teams win just over half their games, but the advantage isn’t as strong as it used to be. Historically, from the 1970s through the early 2010s, home teams won close to 57–60% of the time. Over the past few seasons, however, that edge has diminished, and since 2019 the win rate for home teams has hovered around 52–53%. That’s only a slight edge above random chance, meaning that while playing at home still provides some benefit, it’s no longer the near-automatic bump that bettors could count on in past decades.
For handicapping, this decline matters. Oddsmakers once routinely gave home teams a standard three-point edge in the spread, but in today’s market that figure has been cut in half, closer to 1.5 points. Across the league the numbers show that betting purely on the home team is no longer profitable. Successful bettors now weigh matchup-specific factors like travel distance, rest days, injuries, and team quality far more heavily than the simple fact of where the game is played.
https://www.covers.com/nfl/home-field-advantage#:~:text=On average%2C NFL home teams,where the game is played.