Voting Systems in WA

State elections

There are different voting systems for each house of Parliament in Western Australia.

Voting system for the Legislative Assembly    

Candidates are elected to the Legislative Assembly through full preferential voting. This is a system whereby a candidate must poll an absolute majority of the total formal votes (in excess of 50% in order to be elected.)

This system is characterised by the elector numbering all squares on the ballot paper in order of preference. The ballot paper markings should clearly reflect the elector’s intention.

If, after all first preference votes have been counted, no candidate has obtained an absolute majority of all formal votes, then the candidate with the fewest number of first preference votes is excluded from the count. The excluded candidate’s second preference votes are then distributed to the remaining candidates at this stage.

If, after that exclusion, no candidate has obtained an absolute majority of formal votes, the next remaining candidate with the fewest votes is excluded and all of his or her votes (second preferences and those received from the previously excluded candidate) are distributed to the remaining candidates.

The process is continued until one candidate is elected by obtaining an absolute majority of formal votes. The absolute majority is calculated excluding informal and exhausted votes. To see a diagram explaining the steps involved in this process click here.  

Changes to Voting in the Legislative Council    

Changes to the Electoral Act 1907 which were made since the 2021 State General Election, will result in changes to the voting system for the Legislative Council.

The group voting ticket system and full preferential voting have been abolished and replaced with optional preferential voting in the Council.

These changes mean that electors can vote for one or more preferred groups above the horizontal dividing line on the ballot paper, or at least 20 candidates below the line, to cast a formal vote.

The abolition of the group voting ticket system brings Western Australia in line with the Australian Senate and the upper houses in New South Wales and South Australia.

Under the now abolished group voting ticket system, electors were often unaware that their vote would be used to elect a candidate they did not necessarily wish to elect. Now electors can specify exactly who they want to preference.

Two or more candidates may still form a group.

The new ballot paper will include registered party groups, followed by other groups (two or more candidates), followed by ungrouped candidates. However, only groups with 5 or more candidates are entitled to a square above the line on the ballot paper.

How the Candidates are elected    

To be elected as a member of the Legislative Council, a candidate must receive enough votes to equal a quota.

A quota is calculated using the following formula:

If the quota is not reached the candidate with the least number of votes is excluded and their votes redistributed according to the second preference shown on the ballot paper by the elector.

This process continues until a candidate reaches a quota.

Candidates, who receive a number of votes equal to or greater than the quota are elected immediately. Any votes of these elected candidates, which are surplus to the quota, are transferred to the remaining candidates preferenced on the ballot paper at a reduced value known as a transfer value.

This process is repeated until a candidate reached the quota and is elected, and again until all 37 vacancies are filled.

At the end of the count, if the number of candidates left in the count is equal to the number of remaining vacancies, each of these candidates are elected, regardless of whether the candidate has received a number of votes to reach the quota.  


Filling vacancies in the Legislative Council 

If a member, or members, of the Legislative Council vacate their position, before a State general election, the process to fill the vacancy is set out in the Electoral Act 1907.

His Excellency the Governor of Western Australia will inform the Electoral Commissioner of the vacancy or vacancies. Once informed the Electoral Commissioner will determine if it is practicable to fill the vacancy.

If it is, the Commissioner will advertise the vacancy and Qualified People have 10 days to nominate for the vacancy. To be a 'Qualified Person' they must be: a person who was a candidate who stood for the previous election, did not withdraw from, and was not elected at that election; and have not become a member of the Council since that election; and are qualified to be elected and are not disqualified from being elected as a member of the Council.

After the 10 day period has expired one of three things will occur:


If only one Qualified Person nominates for a vacancy they will be declared elected by the Electoral Commissioner and His Excellency the Governor of Western Australia will be informed.


If more than one Qualified Person nominates for a vacancy a re-count of the votes previously cast in the election will be occur, excluding the member (or members) who vacated their position.

The re-count will follow the methodology explained above in the Voting system for the Legislative Council section and the successful candidate will be declared elected by the Electoral Commissioner and His Excellency the Governor of Western Australia will be informed.


If no Qualified People nominate for a vacancy, His Excellency the Governor of Western Australia will be informed and will then issue a writ for a fresh election in the region concerned to fill the vacancy.

To see a diagram explaining the steps involved in this process click here.    

Local government elections

Optional preferential voting – Changes in voting 2023
In 2023, local government elections in WA moved to optional preferential voting. It is similar to how voting is done in State and Federal elections. 

Under the optional preferential voting system, voters number candidates in the order of their preference. You have the choice to:

  • vote for one candidate - by putting a 1 next to their name
  • vote for some candidates - by numbering several candidates in the order of your preference
  • vote for all candidates - by numbering all the candidates in the order of your preference 

Single vacancy elections
Under the optional preferential voting system, a candidate will need the support of a majority of voters to be elected. In order to achieve this, if no candidate has a majority of the first preferences, the lowest placed candidate would be eliminated and their preferences would be distributed to the voter’s next most preferred candidate. This is the same allocation of preferences that occurs in elections for the Legislative Assembly and House of Representatives.

As a result, the elected candidate is the most preferred candidate of a majority of voters. 

Multiple vacancy elections
Under the optional preferential voting system, the councillors elected will be representative of a proportion of the vote by achieving a quota of vote. This is the same as elections for the Legislative Council and Senate.

Where a candidate has more votes than this quota, their excess votes will be distributed at a reduced value according to their voter preferences, if any. Likewise, if no candidate has met the quota, the lowest placed candidate is eliminated and their voter preferences are then given to the next most preferred candidate, if any.