Labor’s dominant victory in the 2025 federal election, winning 94 of 150 seats with just 34.56 per cent of first preferences, has again shone a spotlight on Australia’s preferential voting system.
Those on the right have called for Australia to examine a return to first past the post voting, which has not been used at a federal level since the Commonwealth Electoral Act was passed in 1918 – ironically, as a response to conservative vote splitting rather than as a democratic reform in its own right.
Calls for renewed electoral reform came after the Liberals and Nationals were ahead in 55 seats after first preferences, only to end up with 43 seats – the Coalition’s lowest return since the first election contested by the newly formed Liberal Party in 1946 and its lowest percentage of seats ever.
First past the post, in which the winner of any electoral race is simply the candidate with the most votes, is used to some extent in 72 nations recognised as a United Nations member state. This ranges from exclusive use in countries ranging from Azerbaijan to Zambia, through to one legislative chamber like in the United Kingdom with the House of Commons, through to use in certain states and territories across the United States. It is also used in mixed systems in places like Japan and South Korea.
Instead, Australian residents select their individual Member of Parliament (MP) – who sits in the House of Representatives – by preferential voting, in particular the instant-runoff system. Under this method, voters rank candidates in order of preference, allowing votes for eliminated candidates to be redistributed until a single candidate achieves a majority.
While it is the right that has called for Australia to look at first past the post voting once more, it is intriguing because, in the UK, preferential voting – usually referred to as the alternative vote or “AV” system – is a cause for left-leaning parties, including Labour.
In the modern era, a switch to the alternative vote system is most closely linked to the centre-left Liberal Democrats. A referendum on the system was held in 2011 as part of a Lib Dem coalition agreement with the Conservative Party in 2010. Two-thirds of voters, off a low turnout of 42.2 per cent, rejected the proposal.
So how would the last four decades of Australian elections have looked under first past the post instead of preferential voting?
Using data from the Australian Electoral Commission, here is how the House of Representatives has looked after every election since 1984 (when the chamber increased by 24 seats to 148):
However, if it had been conducted under first past the post rules, the chamber would have looked like this:
Remarkably, it means that the Coalition would have had most seats at every election from 1996 to 2022, except for 2007 – the Kevin07 tsunami – when they would have been tied with Labor on 74 apiece.
It also means that the 2025 election was the first time since Paul Keating’s “sweetest victory of all” in 1993 that Labor would have claimed an overall majority of seats under first past the post.
While Labor would have been better served under first past the post through the 1980s, it has swung around to the centre-right parties in the years since. Here is how the results would have changed and the trend:
This does not take into account factors like tactical voting, where a voter who would put one candidate first under a preferential system would instead shift their selection to a candidate more likely to win who still represents most of their values.
In a seat like Ryan, where the LNP’s Maggie Forrest led with 34.61 per cent of the vote after first preferences in 2025, enough voters would be likely to coalesce around either the Labor or Green candidate in order to ensure someone on the left were to represent the seat.
Tactical voting was reportedly widespread in the 2017 UK general election, with an Election Reform Society report suggesting that more than 20 per cent of votes were cast strategically. Even if the number is significantly less than that, it ensured that the Conservatives went from majority to minority government despite a significant increase in both vote share and votes.
Over time, a first past the post system would also likely reshape party behaviour, including which candidates and parties choose to contest seats at all. For instance, the teal movement may have struggled to gain a foothold – although independent candidates did manage to prevail in the 2024 UK general election.
Stay tuned for further examinations of how the Australian House of Representatives would look if different electoral systems from around the world were in use down under.