After nearly three decades of defying the odds and shaking up the pop-punk scene, Sum 41 is officially saying goodbye.

The Canadian rock band is gearing up for its final chapter with the Tour of the Setting Sum, marking the end of an era filled with blistering live shows, rebellious anthems and a fan base that has grown up alongside the band members. With one of its final shows hitting the YouTube Theater in Inglewood on Thursday, Sum 41’s final farewell will be a bittersweet moment for both the band and fans alike.

For bassist Jason “Cone” McCaslin and the others, this isn’t just about closing a door — it’s about celebrating a journey full of incredible highs and some tough lows, all while giving fans one last hurrah.

“It’s emotional,” McCaslin says during a recent phone call. “Every show is basically the last time we’ll ever play in that city or even that country, so we don’t take it lightly. We do our best to make sure we play the songs fans want to hear.”

The tour thus far hasn’t been without its challenges. Last year, frontman Deryck Whibley was hospitalized when a nasty case of COVID-19 turned into pneumonia. In August, Sum 41 was forced to cancel several dates after Whibley sustained a back injury. While the band picked back up this month, the recent health scares pile onto a long list of Whibley’s battles over the years, including two herniated discs from a 2010 injury he sustained while on tour in Tokyo. The physical toll of years on the road, combined with his well-documented struggles with alcohol, has created a turbulent backdrop to the band’s enduring success.

Whibley’s personal journey has been filled with high-profile romances and deep struggles. He was famously linked to Paris Hilton in the early 2000s, when their careers and late-night Los Angeles partying and paparazzi culture were at their peak. He married pop-punk icon Avril Lavigne in 2006, but they split three years later.

After nearly losing his life in 2014 due to years of heavy drinking, Whibley used music as an outlet for his pain and reflection. His forthcoming memoir, “Walking Disaster: My Life Through Heaven and Hell,” set for release Oct. 8, delves into not only the rise of Sum 41 but also his relationships, struggles with addiction and journey through the ups and downs of fame.

However, according to the band, the decision to bring Sum 41 to an end wasn’t driven by internal conflict or drama. Instead, after 27 years of chart-topping hits, sold-out tours and countless accolades, the band felt it was simply time. For McCaslin and Whibley — the two remaining original members — the choice came with a sense of sadness but also fulfillment.

“When we first started talking about ending the band, it was emotional,” McCaslin says. “Sum 41 started in 1996, and it’s something we’ve all been doing since we were teenagers, right into our 40s. Now, we’re just riding the wave, enjoying this last tour and having as much fun as we can. We’re like brothers, and we felt that the time had come.”

Formed in Ajax, Ontario, the band endured the grind of the underground music scene, sending out hundreds of demos and facing rejection from nearly every label. The breakthrough moment came after the band shot a DIY music video for the track “Makes No Difference” on a nonexistent budget. The video showed them pranking people, squirting water guns and goofing around in their suburban town. The carefree, rebellious vibe resonated with suburban skaters and punk kids, and it hit a chord much as the show “Jackass” would a few years later. With the video’s success, the band members sent it out in place of a traditional demo and sparked a bidding war among labels, many of which had previously rejected them. Eventually, they signed with Island Records.

When their debut album, “All Killer No Filler” dropped in 2001, it propelled them into the pop-punk elite. Hits like “Fat Lip” and “In Too Deep” became early-aughts anthems. Over the years, Sum 41 has sold over 15 million records worldwide, earned a Grammy nomination and won multiple Juno Awards. Cemented as a cult favorite of the pop-punk era, it rose alongside bands like Simple Plan, All Time Low, Jimmy Eat World and Paramore.

Now, as the musicians prepare to bow out with “Heaven :x: Hell,” a final double album that captures both their pop-punk roots and heavier metal influences, McCaslin says the band is embracing the opportunity to reflect on what it’s accomplished.

“It’s funny, we never really looked back all that much, but this is forcing us to,” he says. “On tour, we’ve been kind of finding ourselves sitting in a circle together sharing old tour stories and just laughing.”

That ride has included its share of intense and challenging moments. In 2005, the band had to cancel a show in the U.K. due to a London bombing.

Around the same time, a normal day off turned into a tumultuous night of partying in France, culminating in Whibley being arrested after a brawl with security guards. Yet, despite the chaos, the band still performed the next day in front of 50,000 people, thanks to some unexpected help from local authorities. It’s one of many tales that sum up the resilience and unpredictability that have defined Sum 41’s career.

“That morning, we just decided to start drinking — mind you, we were about 24 at the time,” McCaslin said with a laugh. “We walked by the festival grounds we were playing the next day in France. It’s 4 in the morning, and Deryck and I started kicking over signs. At one point, Deryck got on the hood of a car, and it just so happened to be a security car for the festival. A huge fight breaks out, and long story short, Deryck ends up in jail. We were supposed to headline the festival the next day, but luckily the promoter knew the mayor, whose daughter was a massive Sum 41 fan. They got us out, and we made it just in time.”

As for legacy, McCaslin hopes fans remember Sum 41 for the energy it brought to every show.

“We always just wanted people to have a good time. We didn’t take ourselves too seriously. We joke around a lot even onstage, but we always took the music seriously,” he says. “At the core, we really are a live band; that’s what we’re known for.”

For a group that started as suburban kids from Canada, Sum 41 continues to connect with fans in ways that pleasantly surprise them. The recent single “Landmines” has taken U.S. radio by storm, proving that even after 27 years, the music still resonates.

“We didn’t expect it to take off like that, but it’s the best way to go out,” McCaslin said. “We never thought we’d make it this far. We’re just lucky that people cared about our music as much as we did.”