Definition

The longstanding definition of a landslide victory in the UK is securing a majority of at least than 100 seats in Parliament. While newspapers etc have sometimes used the term more loosely, for the purposes of this question the 100 seat majority will remain the defining point.

Resolution

The date of the election is not currently known. The latest date allowed by law is 28th January 2025, but as this would result in the current government sitting for more than 5 years (therefore breaking longstanding conventions) and the election period running over the Christmas holidays, it is widely expected to take place no later than November 2024.

Once the actual election date is known, the question will be set to close at the time the polls close on election day. Resolution will follow once enough results have been released to be sure whether the criteria were reached. This is most likely to be the following day.

My actions

I will kick off betting on this question with a small bet of my own and may change / increase this bet going forwards, but will keep my bets small relative to the size of the market.

https://www.theguardian.com/politics/2023/jun/07/labour-landslide-election-victory-poll-keir-starmer-rishi-sunak-conservatives-constituency-boundaries

Labour on course for landslide election victory, megapoll suggests

Starmer’s party is 12% ahead of Sunak’s Tories, survey based on new constituency boundaries suggests