List of premiers of Ontario by time in office

This is a list of premiers of Ontario in order of time served in office as premier of Ontario as of April 18, 2025. The preceding premier always stays in office during an election campaign, and that time is included in the total. See also List of Ontario political parties by time in office.

List

Rank	Premier	Incumbency	Dates in office	Mandates	Party
1	Oliver Mowat	23 years, 270 days [1]	1872–1896	6	█  Liberal
2	Bill Davis	13 years, 344 days [2]	1971–1985	4	█  Progressive Conservative
3	Leslie Frost	12 years, 188 days [3]	1949–1961	3	█  Progressive Conservative
4	James Whitney	9 years, 229 days [4]	1905–1914 [5]	4	█  Conservative
5	John Robarts	9 years, 113 days [6]	1961–1971	2	█  Progressive Conservative
6	Dalton McGuinty	9 years, 111 days [7]	2003–2013	3	█  Liberal
7	Mitchell Hepburn	8 years, 103 days [8]	1934–1942	2	█  Liberal
8	Howard Ferguson	7 years, 152 days [9]	1923–1930	3	█  Conservative
9	Doug Ford (incumbent)	6 years, 293 days	2018–present	3	█  Progressive Conservative
10	Mike Harris	6 years, 292 days [10]	1995–2002	2	█  Progressive Conservative
11	Kathleen Wynne	5 years, 138 days [11]	2013–2018	1	█  Liberal
12	George William Ross	5 years, 110 days [12]	1899–1905	1	█  Liberal
13	David Peterson	5 years, 97 days [13]	1985–1990	1 *	█  Liberal
14	George A. Drew	5 years, 63 days [14]	1943–1948	3	█  Progressive Conservative
15	William Howard Hearst	5 years, 43 days [15]	1914–1919	0	█  Conservative
16	Bob Rae	4 years, 268 days [16]	1990–1995	1	█  New Democratic
17	John Sandfield Macdonald	4 years, 157 days [17]	1867–1871	1	█  Conservative
18	Ernest Charles Drury	3 years, 244 days [18]	1919–1923	1	█  United Farmers
19	George Stewart Henry	3 years, 207 days [19]	1930–1934	0	█  Conservative
20	Arthur Sturgis Hardy	3 years, 92 days [20]	1896–1899	1	█  Liberal
21	Ernie Eves	1 year, 190 days [21]	2002–2003	0	█  Progressive Conservative
22	Edward Blake	310 days [22]	1871–1872	1	█  Liberal
23	Gordon Daniel Conant	209 days [23]	1942–1943	0	█  Liberal
24	Thomas Laird Kennedy	197 days [24]	1948-1949	0	█  Progressive Conservative
25	Frank Miller	138 days [25]	1985	1 *	█  Progressive Conservative
26	Harry Nixon	91 days [26]	1943	0	█  Liberal

^* Frank Miller's Progressive Conservative Party won a plurality of seats in the 1985 Ontario general election, but the resulting 33rd Parliament of Ontario passed a motion of no confidence against him less than two months into his mandate, replacing his government with David Peterson's Liberal Party. This table counts the 1985 election as a mandate for Miller.

References

1. "Oliver Mowat, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
2. "William Grenville Davis, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
3. "Leslie Miscampbell Frost, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
4. "James Pliny Whitney, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
5. died in office
6. "John Parmenter Robarts, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
7. "Dalton McGuinty, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
8. "Mitchell Frederick Hepburn, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
9. "George Howard Ferguson, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
10. "Michael Harris, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
11. "Kathleen O. Wynne, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
12. "George William Ross, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
13. "David Robert Peterson, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
14. "George Alexander Drew, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
15. "William Howard Hearst, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
16. "Bob Keith Rae, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
17. "John Sandfield Macdonald, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
18. "Ernest Charles Drury, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
19. "George Stewart Henry, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
20. "Arthur Sturgis Hardy, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
21. "Ernie Eves, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
22. "Edward Blake, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
23. "Gordon Daniel Conant, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
24. "Thomas Laird Kennedy, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
25. "Frank Stuart Miller, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.
26. "Harry Corwin Nixon, MPP". Legislative Assembly website. Legislative Assembly on Ontario. Retrieved April 1, 2013.