The first House of Assembly was elected on 4 July 1773 and consisted of 18 members.

In 1893, the Legislature Act abolished the House of Assembly and the Legislative Council and established the PEI Legislative Assembly of 30 members in 15 electoral districts. Each of the province's three counties had 5 electoral districts and each district returned two members - one councillor and one assemblyman. These constituencies remained in effect until a 1966 amendment to the Act, providing for 32 members in 16 districts. The Legislature Act outlined the qualifications for those eligible for members: male British subjects of twenty-one years of age or more. Ineligible to sit as members were: government contractors, clergymen, members of the House of Commons, federal and provincial Crown employees except the Provincial Secretary-Treasurer, the Commissioner of Public Lands, the Attorney-General, Commission of Public Works, if they were elected while holding their office. Qualifications for voters for Councillor stipulated that voters must be male British citizens of 21 years of age or more and possess real estate of the value of $325.00. Qualifications for voters for Assemblyman included male British subject of age 21 years or more, owner or occupier of an estate of a yearly value of at least $6.00, or had worked and lived in the province for one year, or was a resident of Charlottetown or Summerside for one year and paid poll tax. A Speaker is elected from the Members of the Legislative Assembly (MLAs) and presides at all meetings of the Assembly. A 1904 amendment to the Act respecting the Legislature allowed for the election of a Deputy Speaker from the members to act in the absence of the Speaker, although it appears that this did not regularly occur until the 1930s. The 1913 Legislative Assembly Privileges Act outlined the privileges and duties of the elected Legislative Assembly members. This act removed the power of appointing a Clerk from the Legislative Assembly members and vested the power with the Lieutenant Governor in Council. In 1921, the voting franchise was extended to women. The Election Act of 1922 further provided the Lieutenant Governor in Council with the power to appoint a Clerk of the Legislative Assembly and any additional assistant clerks deemed necessary to carry out the business of the Legislative Assembly. The Act also vested the Clerk of the Legislative Assembly as custodian of all records created and related to the Legislative Assembly. The 1940 Legislative Assembly Act provided for more details regarding the election of Speakers and Deputy Speakers in the event of the absence or death of the Speakers. This act also stipulated that the Legislative Assembly should last for 5 years, and no more, and that a session be held once in every year. The qualification of members was laid out in the 1940 act which now included females as well as males. The make-up of the Executive Council and Treasury Board are outlined in this act as well as the Legislative Assembly privileges which are based on those of the House of Commons. The 1948 Act to amend the Legislative Assembly Act outlined the duties of the Clerk of the Assembly as pertains to the Acts of the province. Also, all records of the Assembly were to be deposited in the office of the Clerk. This act also outlined the payments allowed for Members of the Legislative Assembly and Leader of the Opposition for fulfilment of their official duties. In 1963, a Royal Commission on Electoral Reform recommended a provincial Election Act, the creation of a position of Chief Electoral Officer and that the vote be extended to aboriginal peoples of the province. The 1965 Election Act revised the electoral districts, increasing the number of dual member districts from 15 to 16, thus returning 32 members of the Legislative Assembly. A 1967 Election Act amendment changed the qualification age for electors from 21 to 18 years of age. In 1974, the provincial government established the Electoral Boundaries Committee, a legislative committee which recommended the rearrangement of the electoral boundaries for better geographical and population representation, however, no government action was taken. An Election Act and Electoral Boundaries Commission was established in 1993 and in 1994 the Commission presented its report to the Legislative Assembly recommending 30 single member districts. The Electoral Boundaries Act was passed in 1994, providing for 27 single member electoral districts. The 1996 general election was the first to run with 27 single member per riding candidates. Changes were made to the electoral boundary districts again in 2006, returning 27 members in the 2007 general election, the first election following the revised map.