Five prediction markets are moving for very different reasons this week on Kalshi: an election, a movie reboot, and NFL and MLB games.
Chiefs vs Colts
The Colts travel to Arrowhead Stadium for Sunday Night Football in a game that doubles as a return-to-health story for both starting quarterbacks: Patrick Mahomes is back from a torn ACL, and Daniel Jones is back from a torn Achilles.
Kansas City also added reigning Super Bowl MVP running back Kenneth Walker III to its backfield this offseason, and the market already has Kansas City as a clear favorite over an Indianapolis team looking to bounce back from a rough Week 1 loss.
Why It's Worth Trading This Week:
Two starting quarterbacks are getting their first real test since major injuries, in primetime, against playoff-caliber pass rushes.
Our take:
We're leaning toward the Chiefs here. Mahomes at home, with a healthier backfield than a year ago, is a tough matchup for a Colts defense that just gave up 41 points in Week 1: injury questions aside, the supporting cast gap favors the Chiefs.
Brazil's Presidential Race Flips on Kalshi
For the first time since polling began, Senator Flávio Bolsonaro is trading ahead of President Lula da Silva on Kalshi's Brazil presidential election winner contract.
Bolsonaro, running with his imprisoned father's public blessing, has climbed as September surveys from pollsters like AtlasIntel show him edging into the lead for a potential runoff.
Lula, seeking a fourth term at 80, still leads most first-round numbers, so the flip says more about runoff math than about the October 4 vote itself.
Why It's Worth Trading This Week:
The first round lands in three weeks, and every new poll is repricing the contract in real time. The next data drop could move things again before Sunday.
Resident Evil Rotten Tomatoes Score
Zach Cregger's Resident Evil reboot releases on September 18, so this is the week critic reviews start counting. Kalshi's own forecast for the eventual score is about 81 now, even though Cregger's last two films, Barbarian and Weapons, both landed in the low-to-mid 90s on Rotten Tomatoes.
Why It's Worth Trading This Week:
Video game adaptations rarely clear the bar horror directors do, and this is Cregger's first time working inside someone else's universe instead of an original script. That gap between his track record and the genre's history is exactly what makes the score worth a position before the embargo lifts.
Our Take:
We'd lean toward the 80-85 range. Cregger's talents are real, but adapting an established franchise usually costs a few points against an original idea: strong reviews, not necessarily a clean sweep.
The Northern Ireland Question
This contract tracks whether the UK's Secretary of State for Northern Ireland formally calls a border poll on Irish reunification before Jan 1, 2030.
It traded quietly for months until President Donald Trump told reporters in Dublin over the weekend he'd "love to see" a united Ireland "eventually."
Why It's Worth Trading This Week:
UK Prime Minister Andy Burnham has called a referendum "off the table" for now. Expect renewed volume as UK officials keep responding through the week.
Our Take:
It's certainly something to monitor, but we're leaning toward "no" for now. While this is something that multiple parties would like to see, the valuable play is to hold off. The reason for this being 'off the table' is because the Northern Ireland people aren't asking for it. Polls seem to indicate that the Northern Ireland people prefer to stay in the United Kingdom.
Fed Decision This Week
The Federal Open Market Committee meets Tuesday and Wednesday, and Kalshi's September decision contract has swung hard toward a quarter-point increase after August's hotter-than-expected inflation report. A hold was the favored outcome three weeks ago; that flipped after Chair Kevin Warsh's Jackson Hole remarks and this month's CPI print.
Why It's Worth Trading This Week:
Wednesday's announcement is the resolution. The contract has swung by dozens of points twice in the past month, so there's no guarantee the current lean holds until then.
How Prediction Markets Work
Each of these markets works the same way: a contract priced between 1¢ and 99¢, where the price reflects the market's live estimate of that outcome's probability. Traders can buy a "yes" or "no" position and hold it to resolution, or sell early if the price moves in their favor.
Unlike a fixed line, the price updates continuously as new information comes in: a poll, a review, a box score, which is why each of the five contracts above has already moved more than once this week. Don't forget to download the Action Network app for more analysis and picks.
