The Prime Minister's expected resignation date has been pushed back by 3 days, from 18 August 2026 to 21 August 2026, according to the latest Polymarket data. This shift comes as markets now estimate around ~86% probability that Starmer will still be PM on that later date.
The delay in Starmer's anticipated departure suggests the Labour leader may be gaining ground against calls for his resignation, though the prospect of him stepping down by late August remains the strong favourite outcome.