The primary driver behind current Polymarket pricing for the Reserve Bank of New Zealand’s December 2026 decision—where no change leads at 54% implied probability ahead of a 25 basis point hike at 40.5%—is the RBNZ’s September Monetary Policy Statement, which delivered a 25 basis point Official Cash Rate increase to 2.75% amid June-quarter CPI inflation of 4.1% driven by Middle East-related fuel price shocks. The central bank’s data-dependent stance, modeled OCR track signaling gradual normalization toward neutral levels near 3.2–3.3%, and emphasis on assessing prior tightening effects before further moves have kept December expectations balanced, with core inflation measures and wage expectations remaining consistent with the 1–3% target band by mid-2027. Recent Treasury pre-election forecasts highlighting persistent inflation pressures and higher rate paths have reinforced this split, while elevated unemployment at 5.6% and upcoming October data releases on inflation and activity will serve as key catalysts ahead of the December meeting.