PM Starmer's resignation date moved up by 2 days to 15 Sept 2026

· implied p50 shift

Briefing

The Prime Minister's expected resignation date has been moved forward by 2 days, according to the latest Polymarket data. Starmer is now projected to step down as PM on 15 Sept 2026, ~2 weeks earlier than previously forecast.

The shift comes as markets price in a growing likelihood of Starmer's early departure from Downing Street. Traders are now pricing in an ~86% chance Starmer will resign by the new date of 15 Sept 2026.