Watching the 2026 Oscars will be a nailbiter for more than several categories. Since the Academy Awards marks the end of the awards season (and a long one at that for this year), the outcome for much of the show tends to be a foregone conclusion after the results of the BAFTAs, Actor Awards, Golden Globes, and more. While this is indeed the case for, say, One Battle After Another’s Paul Thomas Anderson for Best Director and Hamnet’s Jessie Buckley for Best Actress, there’s a handful of categories where the predicted frontrunner could reasonably lose to the underdog. And that includes multiple topline categories, like Best Actor and Best Supporting Actress.

The biggest upsets at the 2026 Oscars could occur in six places

Best Supporting Actress: Amy Madigan vs. Teyana Taylor vs. Wunmi Mosaku

Among all of the categories for the 2026 Oscars, Best Supporting Actress is the most competitive. Looking at the latest odds (from March 11) from prediction markets, like Kalshi and Polymarket, Amy Madigan (Weapons) has earned around 52% of the bett, while Teyana Taylor (One Battle After Another) has about 25% and Wunmi Mosaku (Sinners) is holding onto roughly 21%.

This three-way race was closer near the beginning of March, but Madigan has since increased her lead after winning the Actor Award for Best Supporting Actress. Earlier in the year, Taylor gained a lot of momentum after winning Best Supporting Actress at the Golden Globes, but she hasn’t been able to maintain that through the season. Meanwhile, Mosaku most recently received the Best Supporting Actress award at the BAFTAs and won as part of the Actor Award for Outstanding Performance by a Cast in a Motion Picture, though she lost to Madigan in the individual category.

Best International Film: Sentimental Value vs. The Secret Agent

Prediction markets have Sentimental Value in the lead, though it doesn’t have the most dominant position as a frontrunner. The Norwegian film holds about 61% of the betting market, with The Secret Agent getting 26% to 34%. This roughly 30-point margin is still substantial for Sentimental Value, but both movies have received major awards so the competition remains close.

While the pair of films are both nominated for Best Picture, Sentimental Value has the edge as far as nominations are concerned, with nods for Joachim Trier (Best Director), Renate Reinsve (Best Actress), Stellan Skarsgard (Best Supporting Actor), and Inga Ibsdotter Lilleaas (Best Supporting Actress). It has claimed spots for Best Original Screenplay and Best Film Editing as well.

By comparison, The Secret Agent has fewer nominations: Wagner Moura for Best Actor and Gabriel Domingues for the new category, Best Casting. So in terms of body of work, Sentimental Value remains the odds-on favorite. That said, The Secret Agent did win Best International Feature Film at the Film Independent Spirit Awards and the most recent Satellite Awards, so it’s not out of the picture.

Best Actor: Michael B. Jordan vs. Timothée Chalamet

As we noted in a piece on Marty Supreme potentially getting shut out at the Oscars, the momentum has greatly shifted toward Michael B. Jordan over the last week. His performance in Sinners garnered him the win at the Actor Awards for Outstanding Lead Actor in a Motion Picture at the beginning of March, and the odds now favor him for the Oscar as we head toward the final stretch. Prediction markets have Jordan at around 56% of the bet while Marty Supreme’s Chalamet having to settle at about 35%.

At this point, it’s hard to say whether Jordan winning or Chalamet winning would be the bigger upset. Chalamet carried a lot of early momentum after earning Best Actor (Musical or Comedy) at the Golden Globes, where Jordan lost to Moura in Best Actor (Drama). Meanwhile, Jordan has been able to sprint into the lead in March, far enough ahead that Chalamet could be considered the underdog. Either way, someone is going to be upset.

Best Supporting Actor: Sean Penn vs. Stellan Skarsgård

For his role as villain Col. Steven J. Lockjaw, Sean Penn has held steady as the frontrunner for Best Supporting Actor ahead of Sentimental Value’s Stellan Skarsgård. Penn has about 70% to 73% of the betting market on Kalshi and Polymarket, compared to Skarsgård’s 20%.

This wasn’t always the case as their positions flipped in late February when Penn won the BAFTA, and he has since maintained his lead with his victory at the Actor Awards. However, Skarsgård was able to capture the Golden Globe earlier in the year and most recently the Satellite Award. If Skarsgård wins the Best Supporting Actor Oscar, which is typically presented at the beginning of the show, that will make Sentimental Value’s win for Best International Film more of a sure bet over The Secret Agent.

Best Cinematography: Michael Bauman vs. Autumn Durald Arkapaw

The prediction markets for Best Cinematography has flipped several times over the last three months. Before the award season started in January, One Battle After Another’s Michael Bauman held the lead before it shifted to Sinners’ Autumn Durald Arkapaw. Their positions then switched again in the middle of February.

That said, prediction markets have Bauman holding a substantial lead at 73% while Arkapaw has an outside shot with roughly 20%. As far as late-game momentum, Bauman earned the win from the American Society of Cinematographers in March 8, which is a strong indication that he will also receive the Oscar. That said, if Arkapaw is able to make a surprise upset, it will give Sinners a push for Best Picture.

Best Picture: One Battle for Another vs. Sinners

With its wins at the Actor Awards, Sinners has a shot at taking home the coveted Best Picture award away from One Battle After Another. Unlike the prediction markets for other categories, Sinners has more or less held 15% to 25% of the bet since the start of the award season, with One Battle After Another maintaining \a massive lead at about 70% to 80%. As of March 11, the former has about 75% while the latter has roughly 20% to 23%, with Sinners gaining a slight amount of momentum.

Still, it will be difficult for Sinners to overcome the its rival, with One Battle After Another having won Best Film at the BAFTAs, the Critics’ Choice Awards, and the Golden Globes (for Best Picture – Musical or Comedy), where Sinners lost to Hamnet for Best Picture – Drama. But the Ryan Coogler-directed film is making a last-ditch charge that could push it toward an Oscar victory.