Prime Minister of Great Britain

Prime Minister of Great Britain
Incumbent The Countess of Strathmore since 21 February 2025
His Majesty's Government
Style	The Right Honourable
Type	Head of Government
Member of	Cabinet of Great Britain Privy Council of Great Britain National Security Council Whitehall Foreign Affairs Council
Residence	10 Downing Street
Appointer	The Sovereign
Constituting instrument	Executive Act 2024
Formation	12th of October 2018
First holder	Colfax County
Deputy	Deputy Prime Minister First Secretary of State
Salary	£15,000 per cycle (July 2024)
Website	10 Downing Street

The Prime Minister of Great Britain is the Head of Government of the Empire of Great Britain. The Prime Minister advises the Sovereign on the exercise of much of the royal prerogative, chairs the Cabinet and selects its ministers. As modern Prime Ministers hold office by virtue of their ability to command the confidence of the House of Commons, they tend to sit as a Member of Parliament. It is the most senior of the Great Offices of State.

The Office of Prime Minister was not originally established by any statute or constitutional document and existed only by long-established convention, whereby the Sovereign appoints as Prime Minister at their pleasure. However, since the Reign of William V, the office was established by law and the Sovereign appointed the Prime Minister by those procedures. In practice, the office is held by the leader of the political party that holds the majority of seats in the Commons.

The Prime Minister also holds the position of First Lord of the Treasury, as well as a member of various councils and boards to represent the interests of His Majesty's Government. Their official residence and office is 10 Downing Street in London.

The longest-serving Prime Minister per overall terms is Prince Victor, Duke of York, who served for 409 days across four terms. He also holds the record for longest single term, recording 231 days consecutively as Prime Minister. The longest-serving Prime Minister to be elected to the position is James Forsyte, The Duke of Warwick, who served for 133 days. The shortest tenure as Prime Minister is held by Charles Wright, The Baron Huntingdon, who served 5 days as Prime Minister during the Huntingdon Caretaker Premiership. The first female Prime Minister was Serafina Sherwood, 1st Duchess of Manitoba: three further female Prime Ministers have since served: Elizabeth Howard-Campbell, 1st Duchess of Edinburgh, Kathrine Grey, The Countess of Argyll, and Josephine Carew-Grey, The Baroness Wilton.

Josephine Carew, The Countess of Strathmore has held the office since 21 February 2025.

Prime Ministers of Great Britain

List of Prime Ministers of Great Britain

Portrait		Prime Minister	Term of Office			Mandate	Party	Government	Sovereign
			Start	End	Duration
​		Colfax County MP x	12 October 2018	1 February 2019	113 days	Appointed	Independent	Colfax County Premiership	Victoria II
		Victor Newton MP x	1 February 2019	15 February 2019	15 days	Appointed		1st Newton Premiership
		Fabian Hardie MP x	15 February 2019	3 June 2019	109 days	Appointed		Hardie Premiership
		Victor Newton MP x	3 June 2019	19 January 2020	231 days	Appointed		2nd Newton Premiership
		Corneliu Flint MP x	19 January 2020	28 March 2020	70 days	Appointed		Flint Premiership
​		Oliver Newman PC MP x	28 March 2020	14 August 2020	140 days	Appointed	Centre	Newman Premiership
​		Sir James Stephenson MP for Brecon and Radnorshire	14 August 2020	18 September 2020	36 days	Appointed Aug. 2020 Election	British Workers'	Stephenson Premiership	Victoria II William V
		Cameron Hanover The Baron Lomond MP for Dublin University UC	18 September 2020	23 October 2020	36 days	Sep. 2020 Election	National Progressive Coalition	1st Lomond Premiership	William V
		Philip Ross MP for Melbourne Ports	23 October 2020	8 November 2020	17 days	Appointed		Ross Premiership
		Victor Hanover The Earl of Pembroke MP for York Central	8 November 2020	12 January 2021	66 days	Nov. 2020 Election	BWP-Ind Coalition	Pembroke Premiership
​		Sir Harold Macmillan MP for Bromley	12 January 2021	14 March 2021	62 days	Jan. 2021 Election	Conservative	Macmillan Premiership
​		Sir Angus Somerset MP for Sevenoaks	14 March 2021	20 June 2021	99 days	Mar. 2021 Election Apr. 2021 Election	British Workers'	A. Somerset Premiership
​		James Sherwood-Somerset The Viscount Spencer MP for York Central	20 June 2021	30 October 2021	133 days	Jun. 2021 Election Aug. 2021 Election	Liberal Democrats	Spencer Premiership
​		Kalara Sherwood-Somerset The Duchess of Manitoba MP for Vancouver Centre	30 October 2021	17 January 2022	80 days	Oct. 2021 Election Dec. 2021 Election	SDLP-BWP Coalition	Manitoba Premiership
​		Victor Somerset The Marquess of Grey MP for York Central	17 January 2022	23 April 2022	97 days	???	British Workers'	Grey Premiership
		Sirch Sherwood-Somerset The 2nd Baron Hastings MP for Vancouver Centre	23 April 2022	26 June 2022	65 days	Apr. 2022 Election		Hastings Premiership
		James Somerset The Earl of Northumberland MP for York Central	26 June 2022	9 July 2022	14 days	Jun. 2022 Election		Northumberland Premiership
		Charles Somerset The Baron Huntingdon MP for Cambridge	9 July 2022	9 August 2022	32 days	Appointed		Huntingdon Premiership
		Joshua Sherwood MP for Prince Edward Island	15 August 2022	7 October 2022	54 days	Aug. 2022 Election		J. Sherwood Premiership	William V Elizabeth III
​		Matthew Somerset The Duke of Somerset MP for Glasgow Central	7 October 2022	7 December 2022	62 days	Oct. 2022 Election	British Royalist	1st Somerset Premiership	Elizabeth III
​		Cameron Romefeller The Baroness Lomond MP for West Dunbartonshire	7 December 2022	31 January 2023	56 days	Dec. 2022 Election	British Federation of Labour	2nd Lomond Premiership
​		Elio Somerset The 1st Baron Exeter MP for Exeter	31 January 2023	5 April 2023	65 days	Jan. 2023 Election	Liberal Progressive	Exeter Premiership	Elizabeth III Edward IX
​		Matthew Somerset The Duke of Somerset MP for Glasgow Central	5 April 2023	24 May 2023	50 days	Apr. 2023 Election	Unity Coalition	2nd Somerset Premiership	Edward IX
​		Elizabeth Howard-Campbell The 1st Duchess of Edinburgh MP for St. James	24 May 2023	27 July 2023	65 days	May 2023 Election	British Constitutionalist	Edinburgh Premiership
		Cameron Romefeller The Viscountess Balloch MP for West Dunbartonshire	27 July 2023	20 September 2023	56 days	July 2023 Election		Balloch Premiership
​		August Lleyton The Earl of Stirling MP for Stirling	21 September 2023	20 November 2023	61 days	Sept. 2023 Election	Heron	Stirling Premiership
		William Somerset The 2nd Viscount Douglas MP for Kensington	21 November 2023	5 March 2024	106 days	Nov. 2023 Election Jan. 2024 Election		Douglas Premiership	Edward IX Charles III
​		Thomas Carew The Baron Knightstone MP for East Devon	5 March 2024	1 July 2024	119 days	Mar. 2024 Election May 2024 Election	Heron Unionist	Knightstone Premiership	Charles III
​
​		Josephine Carew-Grey The Baroness Wilton MP for Tavistock	1 July 2024	2 August 2024	33 days	July 2024 Election	Unionist-British Workers' Coalition	Wilton Premiership
		James Forsyte The Duke of Warwick MP for York Central	2 August 2024	27 August 2024	26 days	Appointed		Warwick Premiership
		Thomas Carew The Viscount Sidmouth MP for East Devon	27 August 2024	8 October 2024	43 days	Aug. 2024 Election	National Government	1st Sidmouth Premiership
		August Carew-Grey The Baron Calder & Wilton MP for County Clare	8 October 2024	9 November 2024	33 days	Oct. 2024 Election	Unionist	Calder Premiership
​		Charles Wright The Baron Huntingdon MP for Orkney & Shetland	9 November 2024	13 November 2024	5 days	Appointed	British Workers'	Huntingdon Caretaker
​		Matthew Somerset The Duke of Somerset MP for Glasgow Central	13 November 2024	5 December 2024	23 days	Nov. 2024 Election	Conservative & Unionist	3rd Somerset Premiership
​		Thomas Carew The Viscount Sidmouth MP for East Devon	6 December 2024	6 January 2025	32 days	Appointed	Unionist	2nd Sidmouth Premiership	Charles III George VII
​		William Somerset The 2nd Duke of Cambridge MP for Kensington	6 January 2025	21 February 2025	47 days	Jan. 2025 Election	Unionist-Heron Coalition	Cambridge Premiership	George VII
​		Josephine Carew The Countess of Strathmore MP for East Devon	21 February 2025	present	2 days	Feb. 2025 Election	Unionist	Strathmore Premiership

Disputed Prime Ministers

In order to be considered a Prime Minister, the individual in question must have accepted an invitation from the Sovereign to form a Government in their name: however, the sole disputed PM did not recieve this invitation, but was still considered the acting-PM, effective in all but name. Sirch Somerset was the effective second-in-command and acted as PM over the pre-election period in August 2022, but due to IRL technological limitations, never recieved an invitation to the palace. The nature of this position is disputed: BWP hardliners continue to refer to Sirch Somerset as the "19th Prime Minister", bumping the subsequent naming convention up by one.

Currently, Sirch Somerset is the only Disputed PM.

Portrait		Prime Minister	Term of Office			Mandate	Party	Government
			Start	End	Duration
​		Sirch Somerset The Viscount Halifax MP for Vancouver Centre	9 August 2022	15 August 2022	7 days	Appointed	British Workers'	Halifax Caretaker

Statistics

Longest single tenures as Prime Minister

Prime Minister	Tenure
Victor NewtonII	231 days
Oliver Newman	140 days
James Sherwood-SomersetI	133 days
Thomas CarewI	119 days
Colfax County	113 days
Fabian Hardie	109 days
William Somerset	106 days
Angus Somerset	99 days
Victor SomersetIV	97 days
Kalara Sherwood-Somerset	80 days
Corneliu Flint	70 days
Victor HanoverIII	66 days
Sirch Sherwood-Somerset	65 days
Elio Somerset	65 days
Elizabeth Howard-Campbell	65 days
Harold Macmillan	62 days
Matthew SomersetI	62 days
August LleytonI	61 days
Cameron RomefellerII	56 days
Cameron RomefellerIII	56 days
Joshua Sherwood	54 days
Matthew SomersetII	50 days
William SomersetII	47 days
Thomas CarewII	43 days
James Stephenson	36 days
Cameron HanoverI	36 days
Josephine Carew-Grey	33 days
August Carew-GreyII	33 days
Charles Somerset	32 days
Thomas CarewIII	32 days
James ForsyteIII	26 days
Matthew SomersetIII	23 days
Philip Ross	17 days
Victor NewtonI	15 days
James ForsyteII	14 days
Charles WrightII	5 days

Longest overall time as Prime Minister (cumulative tenures)

Prime Minister	Tenure
Victor Somerset4	409 days
Thomas Carew3	194 days
James Forsyte3	173 days
William Somerset2	153 days
Cameron Romefeller3	148 days
Oliver Newman	140 days
Matthew Somerset3	135 days
Colfax County	113 days
Fabian Hardie	109 days
Angus Somerset	99 days
August Carew-Grey2	93 days
Kalara Sherwood-Somerset	80 days
Corneliu Flint	70 days
Sirch Sherwood-Somerset	65 days
Elio Somerset	65 days
Elizabeth Howard-Campbell	65 days
Harold Macmillan	62 days
Joshua Sherwood	54 days
Charles Somerset2	37 days
James Stephenson	36 days
Josephine Carew-Grey	33 days
Philip Ross	17 days

Other Records and Statistics

Description	Holder(s)
Most tenures as Prime Minister	Victor Somerset (4)
Longest single tenure of an elected Prime Minister	James Forsyte (133 days)
Every Sovereign's longest serving Prime Minister (cumulative)	Queen Victoria II - Victor Somerset (246 days) King William V - Victor Somerset (163 days) Queen Elizabeth III - Matthew Somerset (62 days) King Edward IX - William Somerset (102 days) King Charles III - Thomas Carew (189 days) King George VII - William Somerset (47 days)
Most Elections won (Prime Minister)	James Forsyte (3) Cameron Romefeller (3) Thomas Carew (3) Matthew Somerset (3) William Somerset (3)
Most Elections won (Party)	British Workers' Party (7)
Prime Minister who represented the most parties while in office	Cameron Romefeller (3: Imperial Labour Party, British Federation of Labour, British Constitutionalist Party) James Forsyte (3: Liberal Democrats, British Workers' Party, Unionist Party)
Prime Minister who represented two parties during a single tenure	Thomas Carew (Heron, Unionist)
Party with the most Prime Ministers	British Workers' Party (7)
Most consecutive tenures of the same party in 10 Downing Street	British Workers' Party (5 Prime Ministers across 5 Sessions of Parliament) Unionist Party (5 Prime Ministers across 4 Sessions of Parliament)
Most consecutive elections won (Prime Minister)	Angus Somerset (2) James Forsyte (2) Kalara Sherwood-Somerset (2) William Somerset (2) Thomas Carew (2)
Most consecutive elections won (Party)	British Workers' Party (4) Heron Party (4) Unionist Party (4)
Longest tenure in Downing Street by party	British Workers' Party (262 days)
Only elected "acclaimed" Prime Minister	August Carew-Grey (September 2023, October 2024)
Prime Ministers who have held all Great Offices of State	Victor Somerset Elizabeth Howard-Campbell William Somerset
Only independent, elected, Prime Minister	Matthew Somerset (April 2023)
Only Prime Minister to have had multiple appointed terms.	Charles Somerset (July 2022, November 2024)
Most Monarchs in service to	Cameron Romefeller (3: King William V, Queen Elizabeth III, King Edward IX) Matthew Somerset (3: Queen Elizabeth III, King Edward IX, King Charles III) William Somerset (3: King Edward IX, King Charles III, King George VII)
Most seperate tenures as PM in a calendar year	Thomas Carew (3, 2024)
Most seperate tenures as PM in service to a single Monarch	Thomas Carew (3, King Charles III)