Whether it’s due to the meteoric rise of fantasy football, hyping of the sports media or the incredible popularity of football in general, public money from casual bettors dominates the NFL betting market. These bettors often overreact to one week of action and place future wagers based on the outcome of a single game. This plays right into the hands of sportsbooks who can accurately predict where they’re going to get action each week and shade their lines accordingly.
Oftentimes, novice NFL bettors end up betting into bad lines because they just watched Tom Brady throw for five touchdowns, Adrian Peterson single-handedly rip apart a division rival or Mark Sanchez buttfumble his way to an embarrassing loss on national television.
At Sports Insights, we monitor and archive the NFL betting trends at seven offshore sportsbooks (CRIS, 5Dimes, GTBets, BetUS, Sports Interaction, Sportsbook.com and Carib Sports). These percentages represent actual wagers (not consensus data) placed by bettors and are crucial in monitoring and understanding the forces that move lines across the sports betting marketplace.
By analyzing our historical archive of NFL betting trends data, we’ve found that whenever the public loads up on one NFL team, it’s been historically profitable to bet the other side of that matchup. To illustrate this, we turned to our Bet Labs software to perform the analysis.
To start, we created an NFL betting system that examined all underdogs that received 20% or less of spread bets since the start of the 2005 season.
The screenshot below displays the results:
This strategy has produced a 57.7% win rate against the spread (ATS) for profit of +14.19 units and a +12.8% ROI. While this is already quite profitable, we can improve results even further by filtering out visitors and focusing solely on home teams.
The screenshot below shows the updated results:
With visiting teams removed, we see ATS win rate improve to 59.4%, pushing units won to +15.45 and ROI to an impressive +16.1%.
Why does Contrarian NFL Betting Work so Well?
One of the biggest differences between sharp sports bettors and squares is that sharps understand the importance of getting the best of the number. Because almost 25% of NFL games finish with a margin of victory of either 3 or 7 points, having tools in your arsenal to get better lines has a real effect on how profitable you’ll be over the course of an NFL season.
Using Bet Labs, we examined how NFL lines move throughout the week to show how one-sided public betting affects line movement.
To perform the analysis, we looked at how lines moved from open to close for all NFL teams who received 20% or less of spread bets. We then did the same analysis for teams who received 21% or more of spread wagers and compared the results.
Line Movement Open to Close
≤ 20% of bets
All Other Games
|Line Gets Better For Favorite||19.1%||42.3%|
|Line Gets Better For Dog||55.4%||26.8%|
Line Gets Better for Favorite: If the Cowboys open as -3 favorites against the Giants and the line closes at Dallas -2.5, we consider that line move to be better for the favorite.
Line Gets Better for Underdog: Using the same example, if the line closes at Giants +3.5 after opening at +3, we’d consider that move to be better for the underdog.
The data above confirms that there is a correlation between one-sided public betting and NFL line movement. More specifically, in games where one team received 20% or less of spread bets, the underdog in that matchup closed with a better line (compared to the opening line) 55.4% of the time. In all other games, underdogs improved from open to close only 26.8% of the time.
Sharp sports bettors understand this concept and exploit public perception by consistently “buying-back” underdogs at better prices.
It’s also interesting to note that Bet Labs uses archived line data from Pinnacle, a market-setting sportsbook. NFL bettors who take advantage of sportsbook shading should be able to find even more value employing this strategy at public books as they typically shade even further off the market consensus.