List of premiers of Alberta by time in office

Premiers of Alberta by time served in office as of May 9, 2016.

Rank	Premier	Incumbency	Years in power	Number of Mandates	Remarks
1	Ernest Manning	25 years, 195 days	1943-05-31[1]—1968-12-12	7 mandates	The longest serving premier, Manning was leader of the Social Credit Party.
2	Peter Lougheed	14 years, 52 days	1971-09-10—1985-11-01	4 mandates	Peter Lougheed was the first Progressive Conservative to become Premier of Alberta and also the only former Leader of the Opposition to become premier.
3	Ralph Klein	14 years, 0 days	1992-12-14—2006-12-14	4 mandates
4	John Edward Brownlee	8 years, 229 days	1925-11-23—1934-07-10	2 mandates	Brownlee resigned as the result of a sex scandal.
5	William Aberhart	7 years, 262 days	1935-09-03—1943-05-23[1]	2 mandates	"Bible Bill" Aberhart was the first Social Credit premier, leading his party from no seats to a majority government in its first election.
6	Arthur Lewis Sifton	7 years, 157 days	1910-05-26—1917-10-30	2 mandates	Sifton resigned as premier to join Prime Minister Sir Robert Borden's federal war cabinet.
7	Don Getty	7 years, 42 days	1985-11-01—1992-12-13	2 mandates	Getty lost his seat in the Alberta legislature in the 1989 provincial election but remained premier and re-entered the legislature through a by-election.
8	Ed Stelmach	4 years, 297 days	2006-12-14—2011-10-07	1 mandate
9	Alexander Cameron Rutherford	4 years, 266 days	1905-09-02—1910-05-26	2 mandates	Rutherford was Alberta's first premier. He and his cabinet were forced to resign due to the Alberta and Great Waterways Railway scandal.
10	Herbert Greenfield	4 years, 102 days	1921-08-13—1925-11-23	1 mandate[2]	The United Farmers of Alberta was led by the president during the 1921 general election. After UFA President Henry Wise Wood and UFA legal counsel John Edward Brownlee declined offers to lead the party, UFA vice-president Greenfield accepted. He did not have a seat in the legislature but was sworn in as Premier and successfully contested a by-election.
11	Charles Stewart	3 years, 287 days	1917-10-30—1921-08-13	0 mandates	Stewart was the province's last Liberal premier.
12	Harry Strom	2 years, 272 days	1968-12-12—1971-09-10	0 mandates	Strom was the last Social Credit premier of Alberta.
13	Alison Redford	2 years, 167 days	2011-10-07—2014-03-23	1 mandate
14	Richard Gavin Reid	1 year, 55 days	1934-07-10—1935-09-03	0 mandates	Reid was Alberta's last United Farmer premier.
16	Rachel Notley	351 days	2015-05-24	1 mandate	Notley is the first NDP Premier
15	Jim Prentice	251 days	2014-09-15—2015-05-24	0 mandates	Prentice was Alberta's last Progressive Conservative premier.
17	Dave Hancock	176 days	2014-03-23—2014-09-15	0 mandates	Hancock was chosen as interim party leader during a leadership election.

Graphical representation

Colour Key
	Alberta Liberal Party
	United Farmers of Alberta
	Social Credit Party of Alberta
	Progressive Conservative Association of Alberta
	Alberta New Democratic Party

Notes

1. There was no Premier of Alberta from May 23 until May 31, 1943, due to the death of Premier William Aberhart
2. The United Farmers of Alberta won the 1921 election without an MLA leader, but Greenfield was made leader immediately after it, and that election is counted here as having been won by Greenfield.