The 4th Alberta Legislative Assembly was in session from February 7, 1918, to June 23, 1921, with the membership of the assembly determined by the results of the 1917 Alberta general election held on June 7, 1917. The Legislature officially resumed on February 7, 1918, and continued until the fourth session was prorogued on April 19, 1921 and dissolved on June 23, 1921, prior to the 1921 Alberta general election. The 4th Assembly would be the final time the Alberta Liberal Party would hold government, being replaced by the United Farmers of Alberta following the 1921 general election.