ORCHARD PARK, N.Y. – On Saturday, even Buffalo Bills fans were given Denver Broncos souvenir merchandise on United Airlines flight No. 3047.

With the Broncos taking on the host Bills to open the playoffs Sunday at Highmark Stadium in Orchard Park, United Airlines added non-stop flights to its schedule heading from Denver to Buffalo on Saturday and back Monday. When brothers Ethan Miller, of Castle Rock, and Dillan Miller, of Lone Tree, stepped on the plane, they were welcomed by swag on their seats that included Broncos towels, beanies and trading cards.

But there also were a smattering of Bills fans on the flight.

“They just left them behind,’’ Ethan said of the giveaways.

It was a festive atmosphere when passengers left Denver in the late morning and arrived in Buffalo in the late afternoon. Broncos cheerleaders and Miles the Mascot were on hand in Denver to send them off. Then there was plenty of enthusiasm on the flight.

“It was a party vibe,’’ said Sarah Stapp of Denver, on the flight with husband Hoke Stapp. “Lots of cheering. Everybody is super excited for the game.”

The Broncos (10-7), the seventh seed in the AFC, are making their first playoff appearance since winning the Super Bowl in the 2015 season. Standing in their way are the No. 2 Bills, a 8.5-point favorite.

With Denver’s postseason drought finally over, Broncos fans have been arriving in Western New York from all over the place for Sunday’s game. But not all fully bleed orange.

Casey Price of Phoenix, flew in and met up with Ira Simpson and his wife Lynette of Raton, N.M., who also are season-ticket holders. Casey and Lynette are avid Broncos fans. As for Ira, let him explain.

“I grew up here in New York,’’ Ira said while visiting Niagara Falls with the other two. “I’ve been a Bills fan since I was a little kid. Then I moved out West and the only team that was consistently covered was the Denver Broncos. So they’re my second-favorite team.”

Ira Simpson was wearing a Von Miller No. 40 jersey, so at least that did provide a nod to his second-favorite team. The edge rusher starred for the Broncos from 2011-21.

As for Matt Allen, despite living in Littleton, he is a Bills fan, and the Broncos do not get a runner-up nod. Allen, while growing up in Minnesota, became enamored watching the Bills teams of the early 1990s that went to four Super Bowls but lost them all.

Allen, 50, has lived in Colorado since 2000 but makes a point to go each season to the Bills’ home opener. He arrived Thursday at the Denver airport for his flight to Buffalo dressed in Bills gear.

“I got a few looks in the airport coming here,’’ he said.

So, when is Allen’s return ticket to Denver?

“I booked a flight home Monday, January 20 because I figure the Bills are going to play two games here,’’ said Allen, referring to Buffalo being assured of having another home game next weekend if they beat the Broncos.

Living in Colorado, Allen did at least acknowledge what the Broncos have done this season under second-year coach Sean Payton.

“Broncos fans might be excited that they’re going into the playoffs but there is a little timidness (on facing the Bills),’’ Allen said. “But look at where they were last year. Sean Payton has turned the team around.”

Allen was speaking at the Big Tree Inn, a bar and restaurant down the street from Highmark Stadium that has been packed this weekend with Bills fans. There has been plenty of optimism there about what their team will do Sunday.

“Bills by a billion,’’ was the prediction from bartender Larry Dempsey.

Visiting fan Tim Smith said the Broncos will “crumble” just like tables that avid Buffalo fans, known as the Bills Mafia, have been known to jump on and break. Brian Duffek, who owns the Big Tree Inn along with his wife Jennifer, said it’s “going to be a long day” for the Broncos.

The Big Tree Inn, which was founded in 1980 and was bought by the Duffeks in 2018, long has been known as a hangout for Bills players. When Buffalo was going to those Super Bowls three decades ago, stars on the team regularly would visit.

There is a Jim Kelly Tuna Melt on the menu, and Dempsey said the Hall of Fame quarterback still shows up at The Big Tree and has that sandwich. Another regular visitor is said to be the Hall of Fame wide receiver Andre Reed.

When the late Hall of Fame running back O.J. Simpson played for the Bills from 1969-77, the restaurant had not yet opened. But Simpson, who died last April, showed up at The Big Tree Inn in October 2021 before attending a Bills game and was cheered by hundreds of onlookers. Simpson continued to be revered by many in Buffalo despite his infamous post-football history.

As for current Bills players, Brian Duffek said they don’t come in that much because they don’t like being bothered by fans pointing cell-phone cameras. Also, scarce this weekend at The Big Tree Inn have been Broncos fans.

“Haven’t seen any,’’ Smith said.

But there still have been plenty of fans in the area this weekend wearing Broncos gear. Francesco Holm, of Denver, was decked out in a No. 10 Bo Nix jersey.

“There were a bunch of Bills fans on my flight, and they were saying, ‘Bo Nix sucks. Take it off,’’’ said Holm, 20, who had flown in after visiting Florida. “But it was lighthearted.”

Holm moved from Germany to Denver when he was 4 and has been a Broncos fan ever since.

“This is my first playoff game in nine years and my last one was when I was 11,’’ he said. “I couldn’t miss this for the world. I’m extremely optimistic.”

Mike Perez, of Brighton, perhaps brought more Broncos gear to Buffalo than any traveling fan. Perez was wearing a Broncos retro cap and carrying a special case that held four other caps.

“Sometimes you don’t know which one to wear,’’ said Perez, also noting he brought three different beanies.

Perez, 39, is a longtime fan who paid $1,600 for a ticket to the Broncos’ 43-8 loss to Seattle in Super Bowl XLVIII in February 2014 and $2,400 for a ticket to their 24-10 win over Carolina in Super Bowl 50 in February 2016. So, the fact Perez, traveling with Valentine Ramirez of Brighton, both paid $310 for a ticket for Sunday’s game, he considered no big heal.

“It’s been a long time since they’ve been in the playoffs,’’ Perez said. “Hopefully, we can see these guys get a win.”

Hoke Stapp was thinking ahead and bought two tickets for $150 apiece before the Broncos clinched the playoffs with a 38-0 win over Kansas City last Sunday. He said he would have sold them had Denver lost that game.

Ethan and his brother bought tickets for $400 apiece in the corner near the end zone. He wants to be in a similar position as Dec. 28, when he attended Denver’s 30-24 overtime loss at Cincinnati along with his father Alex and Broncos receiver Marvin Mims Jr. scored on a 51-yard touchdown in the third quarter.

“I was the guy who high-fived Marvin Mims when he scored on that long touchdown along with my dad,’’ Ethan said.

Ethan Miller, who also attended Denver’s previous two Super Bowls, is fired up to see the team finally back in the playoffs. He and his brother on Saturday showed off at the Buffalo airport the towels, beanies and trading cards they received on the United flight.

But what about those Bills fans who also were on the flight?

“We had a handful of Bills fans, and we booed them,’’ said Sarah Stapp.