The Federal Reserve’s September meeting just went from “maybe” to “almost certainly.” Polymarket bettors are now pricing in an 83% probability that the Fed will raise interest rates by 25 basis points when the FOMC wraps its two-day meeting on September 16, a dramatic jump from the 50-60% range just a week ago.
The catalyst was August’s core CPI data, which came in at 0.3% month-over-month, overshooting the 0.2% consensus forecast.
The numbers behind the shift
As of September 12, Polymarket’s odds for a 25 basis-point hike sat around 78-80%, with the number continuing to climb toward the 83% figure in subsequent trading sessions. Kalshi, the regulated prediction market competitor, showed closely aligned estimates. CME FedWatch futures, the traditional benchmark for rate expectations, actually ran slightly hotter at around 85-86%.
When you average across venues, the cross-platform aggregate landed at roughly 81.3% after the CPI print dropped.
