The No. 2 seed Buffalo Bills are gearing up for a Sunday wild-card playoff matchup against the No. 7 seed Pittsburgh Steelers, and despite game-time temperatures predicted to drop as low as 23-degrees, the Bills can count on the "Bills Mafia" to turn out in droves.

"Bills Mafia" was coined in 2011 by diehard Bills fans Del Reid, Breyon Harris and Leslie Wille. It started as an inside joke on X, formerly Twitter, and has transformed into a beloved community that's embraced by the franchise and players.

Although the term "Bills Mafia" may conjure up images of Buffalo fans jumping through folding tables at pregame tailgates, the beloved fan base is much more than just a rowdy crowd.

Here's everything you need to know about "Bills Mafia":

What is 'Bills Mafia'?

In short, "Bills Mafia" refers to the Buffalo Bills fan base. But for that fan base, "Mafia" means family. And that family is among the most gracious in the NFL, constantly giving back to the community and to charitable causes championed by Bills players and even players from opposing teams. 

NFL STATS CENTRAL: The latest NFL scores, schedules, odds, stats and more.

In 2020, the Bills filed to trademark "Bills Mafia."

"We felt like we needed to embrace this, because it had really turned into a community spirit," Ron Raccuia, former executive vice president of the Bills' parent company, Pegula Sports and Entertainment, said at the time. "Our players and our coaching staff have really been engaged with it, and it just became very natural."

How did 'Bills Mafia' start?

Following a 19-16 overtime loss to Pittsburgh on Nov. 28, 2010, Bills receiver Stevie Johnson posted a tweet questioning his faith after he dropped what would have been the game-winning touchdown pass. NFL insider Adam Schefter retweeted Johnson's viral postgame tweet nearly a day later, leading Reid and his friends to troll Schefter with old news updates labeled with the hashtag, #SchefterBreakingNews. Schefter subsequently blocked them.

After the season concluded, Reid encouraged the #BillsMafia to follow all the fans blocked by Schefter in the summer of 2011. The name was born and it continued to build momentum the following season: "Training camp rolled around that year, players started using it. Stevie (Johnson) started using it, Nick Barnett was using it, Fred Jackson was using it. It just blew up from there," Reid recalled in November.

Is 'Bills Mafia' a charity?

No, the fan base is not a charity, but "Bills Mafia" loves going out of the way to help others. They take pride in lending a helping hand, whether in the form of a supportive message or a simple donation, large or small.

"Your fandom can change the life of someone else for the better. That’s what’s so awesome about Bills Mafia, is that we've all kind of embraced this perspective," Reid told USA TODAY Sports in 2021. "We make a difference, and it's something I'm so proud of."

When the Cincinnati Bengals won a late-season game in 2017 that helped the Bills sneak into the playoffs for the first time in 17 years, Bills fans poured $415,000 into Bengals quarterback Andy Dalton's foundation for seriously ill children. In return, the Dalton family donated to the pediatric department of Buffalo's Roswell Park Comprehensive Cancer Center.

When Baltimore Ravens quarterback Lamar Jackson was unable to finish a 2021 playoff game in Buffalo, Bills fans donated nearly half a million dollars in his honor to the Louisville chapter of Blessings in a Backpack. The cause reminded them of Pancho Billa, aka Bills superfan Ezra Castro, who died from cancer in 2019. Every year, Bills fans raise money for Pancho’s Packs because Castro’s dying wish was for people to not send flowers but fill backpacks for children in need.

After Bills quarterback Josh Allen lost his grandmother in 2019, fans donated more than $1.4 million to John R. Oishei Children’s Hospital in Buffalo, leading to the Patricia Allen Pediatric Recovery Wing on the hospital’s 10th floor.

"Buffalo Bills fans and charity kind of go together at this point, like peanut butter and jelly," Kristen Kimmick, the founder of Bills Mafia Babes, told USA TODAY Sports in 2021. "It's literally like the cool thing to do in Buffalo is to be kind and charitable."