List of prime ministers of the United Kingdom by tenure start

This article lists each Prime Minister of the United Kingdom by order of their tenure start. There is a difference in numbering due to Prime Ministers being in office for different, non-consecutive terms; for example, the current Prime Minister Boris Johnson is the 77th Prime Minister, but just the 55th person to hold this office.[1]

Sir Robert Walpole is generally regarded as the de facto first Prime Minister of Great Britain. While serving multiple, non-consecutive terms have been frequent throughout history, that practice has generally died out in recent times, with Harold Wilson being the last Prime Minister to do so nearly 50 years ago.

Ordered by tenure, by person

#	Prime Minister	Term Start	Terms in Office	Tenure Length	Political Party
1	Sir Robert Walpole	1721	1	20 years, 314 days	Whig
2	The Earl of Wilmington	1742	1	1 year, 119 days	Whig
3	Henry Pelham	1743	1	10 years, 191 days	Whig
4	The Duke of Newcastle	1754	2	7 years, 205 days	Whig
5	The Duke of Devonshire	1756	1	225 days	Whig
6	The Earl of Bute	1762	1	317 days	Tory
7	George Grenville	1763	1	2 years, 85 days	Whig (Grenvillite)
8	The Marquess of Rockingham	1765	1	1 year, 113 days	Whig (Rockinghamite)
9	The Earl of Chatham	1766	1	2 years, 76 days	Whig (Chathamite)
10	The Duke of Grafton	1768	1	1 year, 106 days	Whig (Chathamite)
11	Lord North	1770	1	12 years, 58 days	Tory (Northite)
12	The Earl of Shelburne	1782	1	266 days	Whig (Chathamite)
13	William Pitt the Younger	1783	2	18 years, 343 days	Tory (Pittite)
14	The Duke of Portland	1783	2	3 years, 82 days	Whig / Tory (Pittite)
15	Henry Addington	1801	1	3 years, 54 days	Tory (Pittite)
16	The Lord Grenville	1806	1	1 year, 42 days	Whig
17	Spencer Perceval	1809	1	2 years, 221 days	Tory (Pittite)
18	The Earl of Liverpool	1812	1	14 years, 305 days	Tory (Pittite)
19	The Viscount Goderich	1827	1	144 days	Tory (Canningite)
20	George Canning	1827	1	119 days	Tory (Canningite)
21	The Duke of Wellington	1828	2	2 years, 320 days	Tory
22	The Earl Grey	1830	1	3 years, 229 days	Whig
23	The Viscount Melbourne	1834	2	6 years, 255 days	Whig
24	Sir Robert Peel	1834	2	5 years, 57 days	Conservative
25	Lord John Russell	1846	2	6 years, 11 days	Whig / Liberal
26	The Earl of Derby	1852	3	3 years, 280 days	Conservative
27	The Earl of Aberdeen	1852	1	2 years, 42 days	Peelite
28	The Viscount Palmerston	1855	2	9 years, 141 days	Whig / Liberal
29	William Ewart Gladstone	1868	4	12 years, 126 days	Liberal
30	Benjamin Disraeli	1868	2	6 years, 339 days	Conservative
31	The Marquess of Salisbury	1885	3	13 years, 252 days	Conservative
32	The Earl of Rosebery	1894	1	1 year, 109 days	Liberal
33	Arthur Balfour	1902	1	3 years, 145 days	Conservative
34	Henry Campbell-Bannerman	1905	1	2 years, 122 days	Liberal
35	H. H. Asquith	1908	1	8 years, 244 days	Liberal
36	David Lloyd George	1916	1	5 years, 317 days	Liberal
37	Bonar Law	1922	1	211 days	Conservative (Scot. Unionist)
38	Stanley Baldwin	1923	3	7 years, 82 days	Conservative
39	Ramsay MacDonald	1924	2	6 years, 289 days	Labour / National Labour
40	Neville Chamberlain	1937	1	2 years, 348 days	Conservative
41	Sir Winston Churchill	1940	2	8 years, 239 days	Conservative
42	Clement Attlee	1945	1	6 years, 92 days	Labour
43	Sir Anthony Eden	1955	1	1 year, 279 days	Conservative
44	Harold Macmillan	1957	1	6 years, 281 days	Conservative
45	Sir Alec Douglas-Home	1963	1	363 days	Conservative (Scot. Unionist)
46	Harold Wilson	1964	2	7 years, 279 days	Labour
47	Edward Heath	1970	1	3 years, 259 days	Conservative
48	James Callaghan	1976	1	3 years, 29 days	Labour
49	Margaret Thatcher	1979	1	11 years, 208 days	Conservative
50	John Major	1990	1	6 years, 155 days	Conservative
51	Tony Blair	1997	1	10 years, 56 days	Labour
52	Gordon Brown	2007	1	2 years, 318 days	Labour
53	David Cameron	2010	1	6 years, 63 days	Conservative
54	Theresa May	2016	1	3 years, 11 days	Conservative
55	Boris Johnson	2019	1	1 year, 162 days (incumbent)	Conservative

Ordered by term

#	Prime Minister	Term Start	Term	Tenure Length	Political Party
1	Sir Robert Walpole	1721	1st	20 years, 314 days	Whig
2	The Earl of Wilmington	1742	1st	1 year, 119 days	Whig
3	Henry Pelham	1743	1st	10 years, 191 days	Whig
4	The Duke of Newcastle	1754	1st	2 years and 241 days	Whig
5	The Duke of Devonshire	1756	1st	225 days	Whig
6	The Duke of Newcastle	1757	2nd	4 years and 332 days	Whig
7	The Earl of Bute	1762	1st	317 days	Tory
8	George Grenville	1763	1st	2 years, 85 days	Whig (Grenvillite)
9	The Marquess of Rockingham	1765	1st	1 year and 18 days	Whig (Rockinghamite)
10	The Earl of Chatham	1766	1st	2 years, 76 days	Whig (Chathamite)
11	The Duke of Grafton	1768	1st	1 year, 106 days	Whig (Chathamite)
12	Lord North	1770	1st	12 years, 58 days	Tory (Northite)
13	The Marquess of Rockingham	1782	2nd	97 days	Whig (Rockinghamite)
14	The Earl of Shelburne	1782	1st	266 days	Whig (Chathamite)
15	The Duke of Portland	1783	1st	261 days	Whig / Tory (Pittite)
16	William Pitt the Younger	1783	1st	17 years and 87 days	Tory (Pittite)
17	Henry Addington	1801	1st	3 years, 54 days	Tory (Pittite)
18	William Pitt the Younger	1801	2nd	1 year and 259 days	Tory (Pittite)
19	The Lord Grenville	1806	1st	1 year, 42 days	Whig
20	The Duke of Portland	1807	2nd	2 years and 188 days	Whig / Tory (Pittite)
21	Spencer Perceval	1809	1st	2 years, 221 days	Tory (Pittite)
22	The Earl of Liverpool	1812	1st	14 years, 305 days	Tory (Pittite)
23	The Viscount Goderich	1827	1st	144 days	Tory (Canningite)
24	George Canning	1827	1st	119 days	Tory (Canningite)
25	The Duke of Wellington	1828	1st	2 years and 299 days	Tory
26	The Earl Grey	1830	1st	3 years, 229 days	Whig
27	The Viscount Melbourne	1834	1st	122 days	Whig
28	The Duke of Wellington	1834	2nd	23 days	Tory
29	Sir Robert Peel	1834	1st	120 days	Conservative
30	The Viscount Melbourne	1835	2nd	6 years and 135 days	Whig
31	Sir Robert Peel	1841	2nd	4 years and 304 days	Conservative
32	Lord John Russell	1846	1st	5 years and 237 days	Whig / Liberal
33	The Earl of Derby	1852	1st	299 days	Conservative
34	The Earl of Aberdeen	1852	1st	2 years, 42 days	Peelite
35	The Viscount Palmerston	1855	1st	3 years and 14 days	Whig / Liberal
36	The Earl of Derby	1858	2nd	1 year and 112 days	Conservative
37	The Viscount Palmerston	1859	2nd	6 years and 129 days	Whig / Liberal
38	Lord John Russell	1865	2nd	241 days	Whig / Liberal
39	The Earl of Derby	1866	3rd	1 year and 243 days	Conservative
40	Benjamin Disraeli	1868	1st	279 days	Conservative
41	William Ewart Gladstone	1868	1st	5 years and 77 days	Liberal
42	Benjamin Disraeli	1874	2nd	6 years and 62 days	Conservative
43	William Ewart Gladstone	1880	2nd	5 years and 48 days	Liberal
44	The Marquess of Salisbury	1885	1st	220 days	Conservative
45	William Ewart Gladstone	1886	3rd	170 days	Liberal
46	The Marquess of Salisbury	1886	2nd	6 years and 18 days	Conservative
47	William Ewart Gladstone	1892	4th	1 year and 200 days	Liberal
48	The Earl of Rosebery	1894	1st	1 year, 109 days	Liberal
49	The Marquess of Salisbury	1895	3rd	7 years and 17 days	Conservative
50	Arthur Balfour	1902	1st	3 years, 145 days	Conservative
51	Henry Campbell-Bannerman	1905	1st	2 years, 122 days	Liberal
52	H. H. Asquith	1908	1st	8 years, 244 days	Liberal
53	David Lloyd George	1916	1st	5 years, 317 days	Liberal
54	Bonar Law	1922	1st	211 days	Conservative (Scot. Unionist)
55	Stanley Baldwin	1923	1st	246 days	Conservative
56	Ramsay MacDonald	1924	1st	288 days	Labour / National Labour
57	Stanley Baldwin	1924	2nd	4 years and 213 days	Conservative
58	Ramsay MacDonald	1929	2nd	6 years and 3 days	Labour / National Labour
59	Stanley Baldwin	1935	3rd	1 year and 356 days	Conservative
60	Neville Chamberlain	1937	1st	2 years, 348 days	Conservative
61	Sir Winston Churchill	1940	1st	5 years and 78 days	Conservative
62	Clement Attlee	1945	1st	6 years, 92 days	Labour
63	Sir Winston Churchill	1951	2nd	3 years and 162 days	Conservative
64	Sir Anthony Eden	1955	1st	1 year, 279 days	Conservative
65	Harold Macmillan	1957	1st	6 years, 281 days	Conservative
66	Sir Alec Douglas-Home	1963	1st	363 days	Conservative (Scot. Unionist)
67	Harold Wilson	1964	1st	5 years and 247 days	Labour
68	Edward Heath	1970	1st	3 years, 259 days	Conservative
69	Harold Wilson	1974	2nd	2 years and 33 days	Labour
70	James Callaghan	1976	1st	3 years, 29 days	Labour
71	Margaret Thatcher	1979	1st	11 years, 208 days	Conservative
72	John Major	1990	1st	6 years, 155 days	Conservative
73	Tony Blair	1997	1st	10 years, 56 days	Labour
74	Gordon Brown	2007	1st	2 years, 318 days	Labour
75	David Cameron	2010	1st	6 years, 63 days	Conservative
76	Theresa May	2016	1st	3 years, 11 days	Conservative
77	Boris Johnson	2019	1st	1 year, 162 days (incumbent)	Conservative

References

1. "Boris Johnson becomes 55th Prime Minister of the United Kingdom".