Keir Starmer Out?
Short Answer
Both the model and the market expect Keir Starmer to be out before Sep 1, 2026, with no compelling evidence of mispricing.
1. Executive Verdict
- Formal leadership challenge not triggered despite severe pressure.
- Many Labour MPs oppose a formal leadership contest.
- Starmer faces a leadership crisis after disastrous early May 2026 elections.
- May 2026 King's Speech outlined significant legislative proposals.
- Public approval declined notably before the May 2026 elections.
- A Labour leadership challenge requires nominations from a fifth of MPs.
Who Wins and Why
| Outcome | Market | Model | Why |
|---|---|---|---|
| Before Jun 1, 2026 | 13.0% | 9.7% | Despite pressure, no formal leadership challenge has been triggered, with many Labour MPs opposing a contest. |
| Before Jul 1, 2026 | 45.0% | 33.4% | A formal leadership challenge has not been triggered, and a significant number of Labour MPs oppose a contest. |
| Before Aug 1, 2026 | 73.0% | 61.0% | Despite calls for resignation, no formal leadership challenge has been triggered by Labour MPs. |
| Before Sep 1, 2026 | 84.0% | 75.0% | A leadership challenge has not been triggered, and many Labour MPs oppose such a contest. |
Current Context
Keir Starmer faces a leadership crisis despite remaining Prime Minister. As of May 18, 2026, Keir Starmer continues to serve as the Prime Minister of the United Kingdom, although his leadership is under significant pressure following substantial losses in local elections earlier in May 2026 [^][^][^]. This crisis has intensified with nearly 90 Labour MPs publicly demanding his resignation or a clear timeline for his departure, alongside several junior ministers stepping down from the government [^][^][^].
A formal leadership challenge has not yet been triggered. Under Labour Party rules, 81 MPs are required to initiate a formal leadership contest, a threshold that has not yet been met [^][^][^]. Prime Minister Starmer has explicitly stated his intention to contest any such challenge should it arise [^][^][^]. While potential leadership contenders like Wes Streeting, Angela Rayner, and Andy Burnham have been mentioned in political discussions, a clear consensus candidate among Labour MPs has not emerged [^][^][^].
Starmer is actively working to stabilize his embattled premiership. To counteract the crisis, Starmer is reportedly concentrating on the government's legislative agenda, including preparations for the King's Speech [^]. Additionally, there are indications of a potential shift in Brexit policy, aimed at improving relations with the European Union, as part of his strategy to stabilize his position [^][^].
2. Market Behavior & Price Dynamics
Historical Price (Probability)
Outcome probability
Date
This market has exhibited a predominantly sideways trend, with the price trading within a range of 1.0% to 18.0%. It currently stands at 2.0%, the same as its starting price, indicating no net change in perceived probability over the market's lifetime. The most significant price movement was a spike on May 16, 2026, when the probability jumped by 11.0 percentage points from 2.0% to 13.0%. This surge in perceived risk to Keir Starmer's leadership was driven by news reports that former Health Secretary Wes Streeting intended to run for the Labour leadership should a contest be triggered. Despite this event, the price has since returned to its baseline, suggesting the market's initial reaction was short-lived.
With a total volume of 95,565 contracts traded, the market shows moderate activity, though daily volume appears inconsistent, suggesting periods of low liquidity punctuated by reactions to specific news events. The 2.0% level has acted as a consistent support base, with the price repeatedly returning to this low probability after any upward movement. The peak of 18.0% represents the key resistance level that has not been broken. Overall, the chart indicates a strong market sentiment that Keir Starmer is unlikely to be out, despite the political pressures described in recent news. The brief spike shows traders are sensitive to leadership challenge announcements, but the swift return to a low baseline suggests a durable conviction that he will remain in his post through the market's resolution period.
3. Significant Price Movements
Notable price changes detected in the chart, along with research into what caused each movement.
Outcome: Before Jul 1, 2026
📉 May 18, 2026: 24.0pp drop
Price decreased from 69.0% to 45.0%
What happened: There is no evidence from the provided sources to suggest that social media activity from key figures or viral narratives was the primary driver of the 24.0 percentage point drop in the "Keir Starmer Out?" market on May 18, 2026. Instead, the market movement appears to be primarily driven by traditional news reports on May 18, 2026, indicating that Keir Starmer was defying calls to resign amidst a leadership crisis [^][^]. Specifically, David Lammy stated that Starmer was "not setting out timetable for his departure" [^], and Starmer reportedly "refuses to quit as PM, challenges Labour Party rebels to oust him" [^]. These declarations, coinciding with the market movement, likely reduced the perceived probability of his exit before July 1, 2026. Social media was irrelevant, as no specific activity was identified as a driver.
📈 May 16, 2026: 37.0pp spike
Price increased from 26.0% to 63.0%
What happened: The 37.0 percentage point spike in the "Keir Starmer Out?" market on May 16, 2026, was primarily driven by traditional news reports confirming former Health Secretary Wes Streeting's intention to run for Labour leadership if a contest is triggered [^]. This announcement, reported by Al Jazeera on May 16, 2026, immediately followed Streeting's resignation from government on May 14, 2026 [^][^]. The news coincided with widespread reports that Prime Minister Starmer was considering resigning due to a severe leadership crisis, with some outlets stating he was preparing a dignified departure plan [^][^][^]. This concrete signal of a potential successor significantly increased the perceived likelihood of Starmer's departure. Social media activity was not identified as a primary driver.
📉 May 14, 2026: 10.0pp drop
Price decreased from 42.0% to 32.0%
What happened: No social media activity was identified as a primary driver from the provided sources. The 10.0 percentage point drop in the "Keir Starmer Out?" market on May 14, 2026, was primarily driven by Keir Starmer's public refusal to resign amidst calls for his departure. Starmer explicitly vowed he "won't walk away" from his position [^], despite facing significant pressure after poor local election results [^][^][^][^]. This public announcement directly countered the market's "Out" outcome, significantly decreasing the perceived likelihood of his resignation before July 1, 2026. Social media activity was irrelevant as a primary driver based on the available information.
📈 May 13, 2026: 9.0pp spike
Price increased from 32.0% to 41.0%
What happened: As of mid-May 2026, Keir Starmer was reportedly facing a severe leadership crisis, with over 90 Labour MPs calling for his resignation and multiple ministerial departures [^][^][^]. While this general context explains heightened uncertainty regarding his tenure, the provided sources do not specify any particular social media activity, news announcements, or market events that occurred precisely on May 13, 2026, to cause the 9.0 percentage point spike. Therefore, the primary driver for this specific price movement cannot be identified from the available information. Social media's role in this particular spike cannot be assessed.
Outcome: Before Aug 1, 2026
📈 May 15, 2026: 23.0pp spike
Price increased from 25.0% to 48.0%
What happened: The primary driver for the 23.0 percentage point spike in the "Keir Starmer Out? Before Aug 1, 2026" prediction market on May 15, 2026, appears to be the intense pressure on Starmer following recent political events. On May 11, 2026, reports emerged from outlets like the Daily Mail indicating that Starmer was considering an orderly departure as UK Prime Minister after poor local election results and the resignation of four junior ministers [^]. These developments likely caused market participants to significantly increase the perceived probability of Starmer leaving office before August 1, 2026. Based on the provided information, social media was not a primary driver, with no specific posts identified as initiating or accelerating the price movement.
4. Market Data
Contract Snapshot
- YES resolution: The market resolves to "Yes" if Keir Starmer officially announces an intention to leave or actually leaves the office of Prime Minister of the United Kingdom before July 1, 2026. An "official announcement" must be reported by at least one specified news source and not specify a departure more than a year from the statement.
- NO resolution: The market resolves to "No" if Keir Starmer has not announced an intention to leave or left office by the specified deadline. Temporary absences (e.g., medical leave) or death do not satisfy the criteria for a "Yes" resolution.
- Key dates/deadlines: The market opened on February 5, 2026, and the outcome must occur before July 1, 2026. If no "Yes" event occurs, the market closes by June 30, 2026, at 11:59 PM EDT.
- Special settlement conditions: Resolution is based on information from the Prime Minister's Office or a list of major news agencies. The market will close early if the "Yes" condition is met, and insider trading by employees of source agencies or those with material, non-public information is prohibited.
Available Contracts
Market options and current pricing
| Outcome bucket | Yes (price) | No (price) | Last trade probability |
|---|---|---|---|
| Before Jun 1, 2026 | $0.13 | $0.88 | 13% |
| Before Jul 1, 2026 | $0.46 | $0.55 | 45% |
| Before Aug 1, 2026 | $0.73 | $0.29 | 73% |
| Before Sep 1, 2026 | $0.84 | $0.17 | 84% |
Market Discussion
Traders are actively debating the timing of Keir Starmer's potential departure, with current market odds indicating a high probability (84%) he will leave office by September 2026, but only a 45% chance by July 2026. Those predicting an earlier exit point to news reports and internal leadership discussions, while others dispute the reliability of these sources and suggest Starmer might aim to remain in office at least until after the G7 Summit.
5. What are the key legislative priorities in the upcoming King's Speech, and how might their reception impact Keir Starmer's leadership stability?
| Number of bills in King's Speech | Over 35 bills [^][^][^][^] |
|---|---|
| MPs calling for Starmer's resignation | Nearly 90 MPs [^][^][^][^] |
| MPs needed for formal leadership challenge | 81 MPs [^][^][^][^] |
The May 2026 King's Speech detailed significant legislative proposals. The Speech outlined over 35 bills, featuring key legislative priorities such as an Energy Independence Bill and reforms related to the NHS, police, and special education needs. Additional proposed legislation included the nationalisation of British Steel and financial services regulation reform [^][^][^][^]. However, the Speech's reception was primarily overshadowed by internal Labour party infighting, rather than its specific contents directly influencing Keir Starmer's leadership stability [^][^][^].
Keir Starmer faces a severe, ongoing leadership crisis. This crisis follows significant losses in recent local, Scottish, and Welsh elections, with reports indicating nearly 90 Members of Parliament are calling for his resignation and four junior ministers have already quit [^][^][^][^]. Despite these challenges, Starmer remains in office, arguing against a leadership contest due to potential "chaos." He also highlights that the formal challenge process, which requires 81 MPs, has not been triggered. His continued leadership is largely attributed to the absence of a unified alternative and a formal leadership challenge, contributing to a state of temporary government gridlock [^][^][^].
6. How do potential successors Wes Streeting, Angela Rayner, and Andy Burnham compare in their policy platforms and levels of support within the Parliamentary Labour Party?
| Wes Streeting's Position | Prominent modernizer on the right of the Labour Party, supports public service reform [^][^] |
|---|---|
| Angela Rayner's Support | Well-liked by the party's left-wing base, potential 'stop-Streeting' candidate [^][^][^] |
| Andy Burnham's Popularity | Highly popular among Labour members, viewed as a 'stop-Streeting' candidate [^][^] |
Labour's potential successors show clear ideological divides. Wes Streeting is positioned on the right of the Labour Party as a prominent modernizer, attracting support from those who advocate for public service reform [^][^]. In contrast, Angela Rayner and Andy Burnham are associated with the party's left-wing base and are perceived as potential contenders who could oppose Streeting [^][^]. The Parliamentary Labour Party (PLP) itself is notably divided, with distinct factions supporting Streeting and others aligning with Rayner and Burnham [^].
Challengers Rayner and Burnham could form a united front. Angela Rayner, well-liked by the left-wing base, is considered a significant challenge to Streeting's leadership aspirations [^][^]. Andy Burnham, while popular among Labour members, faces considerable hurdles in returning to Westminster as an MP [^]. Both Rayner and Burnham are seen as figures capable of uniting the soft left and union-aligned factions, potentially forming a 'stop-Streeting' bloc within the party [^].
7. What evidence from recent YouGov and Ipsos polls addresses the narrative of a collapse in Keir Starmer's public approval since the May 2026 elections?
| PM should stand down | 50% (late April 2026, Ipsos [^]) |
|---|---|
| Labour voting intention | 19% (early May 2026 [^]) |
| Labour voting share (2024 GE) | 34% (2024 general election [^]) |
Public sentiment showed a notable decline before the May 2026 elections. As of late April 2026, Ipsos polling indicated that 50% of Britons believed Keir Starmer should step down as Prime Minister. This figure had not changed significantly since autumn 2025, reflecting a persistent level of public dissatisfaction [^].
Starmer's approval ratings dropped significantly, impacting Labour's support. Media reports in early May 2026 highlighted a sharp decline in Starmer's approval rating, which moved into negative territory. Simultaneously, Labour's projected voting intention share stood at approximately 19%, a substantial reduction from their 34% share achieved in the 2024 general election [^].
8. Is there a publicly maintained dataset tracking the number of Labour MPs who have called for Keir Starmer's resignation since the May 2026 elections?
| MPs calling for resignation | At least 86 (as of May 12, 2026) [^] |
|---|---|
| Leadership contest threshold | 81 members [^] |
| MPs opposing leadership contest | 111 [^] |
No official dataset tracks Labour MPs demanding Keir Starmer's resignation. As of May 18, 2026, there is no single official or universally recognized publicly maintained dataset specifically tracking Labour Members of Parliament who have called for Keir Starmer's resignation. However, major news organizations such as LabourList and The Independent actively provide updated trackers of these MPs [^].
Eighty-six Labour MPs called for Starmer's resignation by May 12. Reports by May 12, 2026, indicated that at least 86 Labour MPs had publicly demanded Keir Starmer's resignation or a specified timetable for his departure, following unsatisfactory results in recent local and devolved elections [^]. While this figure exceeds the 81-member threshold required to trigger a leadership contest, there is no unified support for a single challenger at present. Additionally, 111 Labour MPs have signed a statement expressing opposition to a leadership contest at this time [^].
9. What procedural milestones are required under Labour Party rules to trigger a formal leadership challenge against Keir Starmer before September 2026?
| MP Nomination Threshold | 20% (81 out of 403 MPs) [^][^][^][^] |
|---|---|
| Constituency Party Support | 5% of constituency Labour parties [^][^][^] |
| Affiliated Org Support | 3 affiliated organizations (2 trade unions) representing 5% of affiliated membership [^][^][^] |
Challenging the Labour leader requires initial nominations from a fifth of MPs. To initiate a formal Labour Party leadership challenge against Keir Starmer, a challenger from the Parliamentary Labour Party must first secure written nominations from a minimum of 20% of Labour MPs. This currently translates to 81 out of 403 MPs [^][^][^][^]. As the incumbent leader, Keir Starmer is automatically placed on the ballot and is not required to gather nominations [^][^][^][^].
Further support from party units or unions is also required. Once the 20% MP nomination threshold is met, the challenger must then secure additional backing [^][^][^]. This can be achieved through one of two avenues: either from 5% of constituency Labour parties, or from at least three affiliated organizations, with a minimum of two being trade unions, which together represent at least 5% of the affiliated membership [^][^][^].
The NEC determines the official timetable for the leadership election. Following the triggering of a contest, the National Executive Committee (NEC) assumes responsibility for setting the timetable and specific procedures for the leadership election [^][^][^][^]. The available information outlines the conditions under which these procedural milestones are activated, but does not specify a fixed timeline or particular dates for them.
10. What Could Change the Odds
Key Catalysts
Prime Minister Keir Starmer is currently facing a severe leadership crisis following disastrous local election results in early May 2026, which led to Labour losing nearly 1,500 council seats [^] [^] [^] [^] . No one knows how long that will last.">[^][^][^]. As of mid-May 2026, over 90 Labour MPs and several government ministers, including former Health Secretary Wes Streeting, have called for Starmer's resignation or a clear exit timetable, though no formal leadership challenge has been launched [^][^][^][^].
Prediction markets are highly bearish on Starmer's political future, with some platforms pricing a greater than 60% probability of him leaving office by the end of 2026, and significant speculation regarding a potential exit by June 30, 2026 [^] [^] [^] [^] . Predictions & Odds 2026 | Polymarket">[^][^][^][^]. Key upcoming political catalysts include the ongoing debate on the King's Speech in May 2026, the party conference season in early October 2026, and the potential for a challenging autumn budget from Chancellor Rachel Reeves in October/November 2026 [^][^].
Key Dates & Catalysts
- Expiration: April 08, 2026
- Closes: September 01, 2026
11. Decision-Flipping Events
- Trigger: Prime Minister Keir Starmer is currently facing a severe leadership crisis following disastrous local election results in early May 2026, which led to Labour losing nearly 1,500 council seats [^] [^] [^] [^] .
- Trigger: As of mid-May 2026, over 90 Labour MPs and several government ministers, including former Health Secretary Wes Streeting, have called for Starmer's resignation or a clear exit timetable, though no formal leadership challenge has been launched [^] [^] [^] [^] .
- Trigger: Prediction markets are highly bearish on Starmer's political future, with some platforms pricing a greater than 60% probability of him leaving office by the end of 2026, and significant speculation regarding a potential exit by June 30, 2026 [^] [^] [^] [^] .
- Trigger: Key upcoming political catalysts include the ongoing debate on the King's Speech in May 2026, the party conference season in early October 2026, and the potential for a challenging autumn budget from Chancellor Rachel Reeves in October/November 2026 [^] [^] .
13. Related News
Last updated: May 18, 2026, 13:11 UTC
Market Lengthens Timeline on Potential Keir Starmer Exit
The prediction market for the tenure of UK Prime Minister Keir Starmer saw a significant shift on Monday, May 18, 2026, as traders lowered the probability of an imminent departure. Probabilities fell ...
Last updated: May 18, 2026, 13:11 UTC
Starmer Exit Odds Surge for Summer 2026 Amid Political Crisis
The prediction market for Keir Starmer’s tenure as UK Prime Minister saw a significant repricing on Saturday, May 16, 2026, as traders sharply increased the probability of his departure within the nex...
Last updated: May 18, 2026, 13:11 UTC
Keir Starmer Exit Odds Plummet as Leadership Challenge Stalls
Prediction markets tracking the tenure of British Prime Minister Keir Starmer saw a significant repricing on Tuesday, May 12, 2026, sharply lowering the odds of his imminent departure. The shift occur...
Last updated: May 18, 2026, 13:11 UTC
Starmer Departure Odds Rise Sharply After Election Rout
The prediction market for the tenure of British Prime Minister Keir Starmer saw a significant repricing on Sunday, May 10, 2026, as traders drastically increased the odds of his departure within the c...
Last updated: May 18, 2026, 13:11 UTC
Market Lengthens Odds on Starmer Premiership, Prices Down Early Exit
The prediction market for Keir Starmer’s tenure as Prime Minister saw a significant repricing on Friday, May 08, 2026, with the odds of an early departure falling sharply across the board. The contrac...
14. Historical Resolutions
Historical Resolutions: 3 markets in this series
Outcomes: 0 resolved YES, 3 resolved NO
Recent resolutions:
- KXLEAVESTARMER-26MAY15: NO (May 15, 2026)
- KXLEAVESTARMER-26MAY01: NO (May 01, 2026)
- KXLEAVESTARMER-26APR01: NO (Apr 01, 2026)
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