How long did Liz Truss last as UK prime minister

Key facts at a glance

Liz Truss duration at a glance: She was appointed prime minister on 6 September 2022 and resigned on 20 October 2022, making her tenure 7 weeks (45 days) in total.

Evergreen profile: what defines Liz Truss’s time in office

How long did Liz Truss last as UK prime minister? She served for 7 weeks (45 days), from 6 September 2022 to 20 October 2022. This concise period makes her one of the shortest-serving prime ministers in UK history. Her tenure followed Boris Johnson’s resignation and concluded amid market turbulence and internal party challenges. Below, we break down the timeline, context, and factors that shaped the length of her premiership in a lasting, reference-friendly format.

Context before taking office

Truss was elected leader of the Conservative Party in September 2022 and appointed prime minister on 6 September 2022. She entered office with a declared focus on economic reform, fiscal boldness, and reducing the role of the state. Her first days included the announcement of a growth plan that would later become a central event during her time in No 10.

Major events during her tenure

• 6 September 2022: Appointed prime minister; forms government.
• 23 September 2022: Mini-Budget announcement triggers market reaction.
• 3–5 October 2022: Policy U-turns and fiscal interventions begin.
• 14–20 October 2022: Leadership challenges and Conservative by-election losses mount.
• 20 October 2022: Truss announces resignation; Rishi Sunak becomes prime minister.

Why did her tenure last only weeks?

Multiple factors contributed to the short duration: market reactions to unfunded tax plans, loss of parliamentary confidence, internal Conservative Party dissent, and a sequence of policy reversals that eroded her political capital. These dynamics compressed the period of stable governance and made the length of her premiership unusually brief in modern UK politics.

How this duration compares historically

Compared with other postwar prime ministers, Truss’s 45-day tenure is among the shortest. Only caretaker or emergency arrangements have been shorter in the open era. This table positions her tenure within a concise set of reference points for context.

Aftermath and legacy considerations

After her resignation, Truss’s time in office became a case study in rapid leadership turnover and the interaction between economic policy and market confidence. Analysts often reference the 7-week period when discussing reform feasibility, political risk communication, and the stability expectations for advanced economies. The experience also influenced subsequent Conservative leadership approaches and the perceived risk profile of UK fiscal policy.

Commonly asked follow-ups

• How does 45 days compare with other short UK prime ministerial tenures? It is among the shortest, reflecting acute political and market pressure within a modern democratic system.
• Did she serve a full parliamentary term? No; no general election was scheduled, and her term ended due to internal party decisions rather than an electoral cycle.
• What was the immediate trigger for her resignation? A combination of market turbulence, loss of confidence within her party, and a series of rapid policy changes without clear consensus support.

Evergreen takeaways

• Duration: Liz Truss lasted 7 weeks (45 days) as prime minister.
• Dates: 6 September 2022 to 20 October 2022.
• Contributing factors: Policy announcements, market response, party dynamics, and leadership challenges shaped the short tenure.
• Historical context: One of the shortest premierships in modern UK history.
• Legacy focus: Frequently cited in analyses of policy credibility and institutional stability.