federal

FED2026 Redistributions – South Australian Boundaries Finalised

The South Australian redistribution of electoral boundaries has been finalised this morning. The Commission has abandoned a swap of suburbs between Kingston and Mayo, as well as the transfer of an area from Spence to O’Donoghue (formerly Grey). This means that Kingston and O’Donoghue retain their former boundaries without change.

The Draft boundaries released in March produced only minor changes to the boundaries used at the last three federal elections. Those changes have now been reduced with the Spence to O’Donoghue change reversed and the proposed suburbs swap between Mayo and Kingston abandoned.

South Australia was reduced from 11 to 10 House of Representatives seats by the 2017 redistribution. The current redistribution retains 10 seats and was triggered by the rule requiring boundaries to be re-drawn every seven years. The reason for periodic re-draws is to account for differing patterns of population growth, to bring all electorates back within permitted variation from quota.

Barker pushes closer to Adelaide and gains 3,365 voters around Woodchester from Mayo. Grey has been re-named O’Donoghue but proposed boundary changes abandoned. Population growth in the Adelaide Hills has seen Mayo shed voters to Barker and around 6,275 to Boothby. Adelaide’s outer north has also been growing rapidly and Spence has lost 14,043 voters in Brahma Lodge and Salisbury to Makin. Proposed changes to Kingston have been abandoned and Adelaide, Hindmarsh and Sturt retain their unchanged status from the draft phase.

The table below has been now re-calculated for the final boundaries.

South Australia Federal Redistribution – Summary of New Margins
District Old Boundaries New Boundaries Shift
Adelaide ALP 19.1% ALP 19.1% unchanged boundaries
Barker LIB 13.0% LIB 12.7% 0.3 to Labor
Boothby ALP 11.1% ALP 11.1% no change
Hindmarsh ALP 16.3% ALP 16.3% unchanged boundaries
Kingston ALP 20.7% ALP 20.7% unchanged boundaries
Makin ALP 14.7% ALP 15.3% 0.6 to Labor
Mayo (2-Party) ALP 5.0% ALP 4.8% 0.2 to Liberal
Mayo (IND v ALP) IND 14.9% IND 15.5% 0.6 to Independent
O’Donoghue (formerly Grey) LIB 4.6% LIB 4.6% unchanged boundaries
Spence ALP 15.3% ALP 15.2% 0.1 to Liberal
Sturt ALP 6.6% ALP 6.6% unchanged boundaries

Read More »FED2026 Redistributions – South Australian Boundaries Finalised

FED2026 Redistributions – Tasmanian Boundaries Finalised

The new electoral boundaries for Tasmania have been released today.

Reading through the proposed changes, the major changes to Clark, Franklin and Lyons in southern Tasmania have been agreed to. But there are changes in the north with Break O’Day council being moved into Bass.

There is also a proposed name change which has triggered the calling of a new round of comments specifically about changing the name of Franklin to Tongerlongter. As the proposal explains the name –

Following its deliberations, the augmented Electoral Commission proposes renaming the electorate of Franklin in honour of Tongerlongeter (c. 1790-1837), a Poredareme man of the Oyster Bay nation and a prominent Aboriginal leader whose Country encompassed much of south-east Tasmania, including areas within the reconfigured electorate boundaries. The name ‘Franklin’ is proposed to be retired.

Earlier I tweeted that the draft boundaries had been abandoned. That was confusion on my part by opening the wrong map and thinking that was the reason for calling a new round of submissions. It is rare for redistributions to engage in this extra consultation step. It appears the consultation is over the name change alone so the boundaries appear to be otherwise final.

The draft boundaries released earlier this year produced massive changes to the electorates of Clark, Franklin and Lyons. You can read more details in my post on the draft boundaries.

The table below summarises the two-party preferred margins between Labor and Liberal in the five divisions. I’ll go into more detail on the Independent positions in Clark and Franklin inside the post.

Tasmania Federal Redistribution – Summary of 2-Party Preferred Margin Changes
District Old Boundaries New Boundaries Shift
Bass ALP 8.0% ALP 8.3% 0.3 to ALP
Braddon ALP 7.2% ALP 7.2% Unchanged
Clark ALP 20.9% ALP 20.2% 0.7 to LIB
Franklin ALP 19.4% ALP 18.7% 0.7 to LIB
Lyons ALP 11.6% ALP 12.7% 0.9 to ALP

Read More »FED2026 Redistributions – Tasmanian Boundaries Finalised

FED26 Redistributions – Final Boundaries Released for A.C.T.

The final boundaries for the ACT have been released. Maps and numbers of voters transferred have not been released, but I have managed to estimate new margins using data published with the draft boundaries.

In short, nothing much changes. The table below summarise the margins for the ACT’s three electorates.

ACT Federal Redistribution (Final) – Summary of Margin Changes
District Contest Old Boundaries New Boundaries Shift
Bean 2-Party ALP 19.3% ALP 19.4% 0.1 to ALP
Canberra 2-Party ALP 26.4% ALP 26.4% No change
Fenner 2-Party ALP 22.1% ALP 22.1% No change
Bean ALP v IND ALP 0.3% ALP 0.2% 0.1 to IND
Canberra ALP v GRN ALP 19.5% ALP 19.5% No change

There’s more details on each electorate inside the post.
Read More »FED26 Redistributions – Final Boundaries Released for A.C.T.

2026 Federal Redistributions – South Australia

Proposed new electoral boundaries for South Australia have been released. It is a bad day for me to try and analyse them as I have other commitments. But I have done a quick summary of the changes in this post.

The number of seats is unchanged at 10 on and at first glance the boundary changes are minor.

There is one change of electorate name. As the Redistribution Committee describes it –

The Redistribution Committee proposes renaming the electorate of Grey to the electorate of O’Donoghue. This is to honour the legacy of Dr Lowitja O’Donoghue AC CBE DSG (1932–2024), a Yankunytjatjara woman who was the first Indigenous nurse at the Royal Adelaide Hospital, and became a distinguished public administrator, champion for health equity, and Indigenous rights activist. The electorate of Grey was chosen to be renamed due to Dr O’Donoghue’s strong connection to the Anangu Pitjantjatjara Yankunytjatjara (APY) Lands, which are largely located in the electorate of Grey.

More inside the post.
Read More »2026 Federal Redistributions – South Australia

FED26 Redistributions – ACT Draft Boundaries

Draft federal electoral boundaries for the ACT’s three House of Representatives’ seats have been released this morning. The redistribution has been required under the Electoral Act’s seven-year rule where boundaries are periodically re-drawn to bring electorate enrolments back within permitted variation from quota.

The draft boundaries have proved to be more complex than expected. Rather than a simple transfer of voters from the southern seat of Bean to central Canberra with the northern seat of Fenner left unchanged, the Redistribution has adopted a more extensive proposal that alters all three electorates. My estimated new margins are shown below with more detail inside the post.

ACT Federal Redistribution (Draft) – Summary of Margin Changes
Old Boundaries New Boundaries Shift
Bean (ALP v LIB) ALP 19.3% ALP 19.4% +0.1 ALP
Bean (ALP v IND) ALP 0.3% ALP 1.4% +1.1 ALP
Canberra (ALP v LIB) ALP 26.4% ALP 26.1% -0.3 ALP
Canberra (ALP v GRN) ALP 19.5% ALP 19.5% No change
Fenner (ALP v LIB) ALP 22.1% ALP 22.3% +0.2 ALP

Note: The Labor versus Independent calculation for Bean has added the vote for the Independent in Canberra to the vote for Jess Price in Bean. This probably underestimates the support Price might have received in the added areas but it is not really possible to estimate how Price might have polled. After transferring the primary votes I’ve applied the preference distribution for Bean. This produces a 1.4% major which I suspect is a little higher than it should be. I’ll have a think if there is a better method for the final boundaries later in the year.

The method I normally use is to use the ratio of Senate to House vote for the larger parties. That method is not possible in the ACT because the success of Independent David Pocock in the Senate means all other parties have a lower Senate vote than House vote.

More detail on the redistribution and much more on the ins and outs of each division inside the post.Read More »FED26 Redistributions – ACT Draft Boundaries

FED26 Redistribution – Tasmania Draft Boundaries

Last Friday the Australian Electoral Commission issued draft electoral boundaries for Tasmania. It was the first of this year’s round of federal redistributions.

Draft boundaries for the ACT will be released in a fortnight, South Australia some time after the state election to avoid confusion, and a Queensland federal redistribution will get underway in July.

If the Albanese government goes ahead with rumoured plans to increase the size of the parliament, then all five mainland states will require redistributions before the next election. Tasmania and the two territories would be untouched by an expansion of parliamkent.

But first Tasmania.

Full details of the proposed boundaries can be found at the Australian Electoral Commission’s website. This includes details on how to make comment on or object to the new boundaries.

As I will explain in this post, the Redistribution Committee has abandoned its recent habit of engaging in incremental redistributions, boundaries adjusted at the edges to minimise the number of voters transferred between electorates.

In Tasmania, the proposed boundaries re-arrange the electoral geography of southern Tasmania. Just over a quarter of the state’s electors are moved between seats. The southern seats of Clark and Franklin split in two and re-assembled with a series of rotational swaps through the central seat of Lyons.

The Committee has decided to tackle the state’s most peculiar electoral boundary, the division of the southern seat of Franklin in two by neighbouring Clark. All means of transport between the two ends of Franklin pass through Clark, the seat covering all of central Hobart west of the Derwent River. Franklin covers the eastern shore of Hobart, plus Kingston and all populated parts of the state south of Hobart.

That Franklin has evolved this peculiar geography has roots that go back to Federation. When boundaries were first drawn in 1903, Clark (then known as Denison) covered Hobart on the western shore of the Derwent River at a time when few lived to the east. In 1903 Franklin was the state’s largest electorate in area, extending deep into central Tasmania and completely surrounded Denison. The state’s other three electorates were clustered in northern Tasmania.

Over many decades, as the population of southern Tasmania grew faster than the rest of the state, Franklin contracted south. As Hobart grew in the post-war era, new bridges across the Derwent allowed suburbia to spread to the eastern shore. Areas south of Hobart also grew. Incremental boundary changes turned a Franklin that surrounded Denison into an electorate with two distinct ends.

Federal electorates are so large it is difficult to get a single community of interest that covers an electorate. But no electorate in the country is as geographically divided as Franklin. With Clark (formerly Denison) well under quota, expansion was required with the possibility it would make the boundaries for Franklin even more illogical.

So the Committee has gone for a big bang change more likely to cope with future population shifts. Both Clark and Franklin have been split in two and re-arranged with a rotation of voters through the southern part of the central seat of Lyons.

In terms of two-party politics the new boundaries have little impact. But Clark is held by Independent Andrew Wilkie, and Franklin in 2025 saw a strong challenge from Independent Peter George. He has since gone on to win one of Franklin’s seven seats in state parliament. The proposed boundaries for Clark and Franklin drastically re-arrange Independent support.

It’s best for me to explain the change seat by seat. Note: maps have been taken from the redistribution report and are published by the Australian Electoral Commission.Read More »FED26 Redistribution – Tasmania Draft Boundaries

FED25 – A Plethora of Estimated Margins and Problems with the AEC Version

In a pre-Christmas treat for election nerds, the Australian Electoral Commission is about to publish its estimated seat margins for next year’s Federal election.

The 2025 Federal election will be fought on new electoral boundaries following redistributions in New South Wales, Victoria and Western Australia. There has also been a redistribution in the Northern Territory though those boundaries are yet to be formally gazetted into place.

Earlier this month I published my estimates of post-redistribution margins. These are the margins I recommend the ABC should use at the 2025 election. (The post includes links to an alphabetic list of electorates and all new margins plus a new pendulum.

Having been asked my opinion of the AEC’s estimated new margins, I agree with the AEC in 137 of the 150 seats, am in close agreement on another four, but disagree on nine seats to varying degrees.

These nine seats are contests that did not finish as traditional two-party preferred races between Labor and the Coalition in 2022, and where there have been significant boundary changes.

Inside this post I have published a table that includes my estimated margins for these nine seats, as well as the AEC’s, and two other estimates published by prominent election observers, Ben Raue of the Tallyroom website, and William Bowe of the Pollbludger website.

(The AEC’s estimates are now available. You can find them at this link.)

In some entries in the table, the AEC’s estimates differ from the values that Ben, William and I calculated independently. In other entries the different methodologies adopted mean there are a range of possible estimated margins.

In this post I’ll run through detail on where there is disagreement.

But I need to make clear I am in no way suggesting there is a problem with how the AEC will conduct the 2025 election.Read More »FED25 – A Plethora of Estimated Margins and Problems with the AEC Version

FED25 Election – New Seat Margins and Electoral Pendulum

At the 2025 Federal election, more than half of seats in the House of Representatives will be contested on new electoral boundaries.

In this post I summarise the state of play going into the election and provide estimated margins for all seats affected by the redistribution. You can find a listing of margins for all seats at this link.

The above document lists traditional two-party preferred margins for all seats, but also alternative two-candidate preferred margins in seats that were not contests between Labor and the Coalition in 2022.

There were a record 27 seats in 2022 that did not finish as contests between Labor and Coalition candidates. There is every chance this number could increase in 2025, with analysis of results further complicated by the new electoral boundaries.

I’ve tried to create a new electoral pendulum that summarises the party contest for 2025. You can find the pendulum at this link.

The pendulum groups seats by holding party, simplified to Labor, Coalition and ‘Other’ groupings. Within each party grouping, seats are listed in margin order. Second placed party is also shown for seats that were not Labor versus Coalition contests in 2022.

The problem with this layout is that it mixes two-party and two-candidate margins. The ordering allows you to identify marginal seats, but makes it impossible to apply uniform two-party preferred swing to try and predict seat numbers. It is best to skip over the ‘Other’ contest seats in applying two-party swing.

On a third page of the pendulum document I’ve added mini-pendulums that set out margins for Labor versus Others and Coalition versus Others contests. For several electorates where Labor and the Greens compete on first preferences to make the final contest versus the Coalition, I have also provided an estimated primary vote margin.

There’s more about the redistribution and information on how the new margins have been calculated inside this post.Read More »FED25 Election – New Seat Margins and Electoral Pendulum

2024 Federal Redistributions – Draft Northern Territory Boundaries

(22 November – no objections were received for the draft boundaries and they should be gazetted in the new year for use at the 2025 Federal election.)

(4 March 2025 – after a long delay, the new boundaries will be gazetted today allowing them to be used at the soon to be announced federal election. That it has taken so long for an uncontroversial boundary change to be implemented is something that should be looked at in a review of the legislation.)

The final electoral jigsaw piece has been put in place for next year’s Federal election.

Redistributions have been finalised for NSW, WA and Victoria. Today has seen the release of draft boundaries for the Northern Territory.

These draft boundaries are now open for public comment, but as the Redistribution Commissioner’s proposal is the same as every submission suggested, the final stage of the redistribution will simply rubber stamp the draft proposal.

If you want to make a submission or read more detail on the redistribution, you can do so through the AEC’s NT Redistribution site.

In this post I’ll just give a brief summary of the change and estimated new margins for Lingiari and Solomon.Read More »2024 Federal Redistributions – Draft Northern Territory Boundaries

2024 Federal Redistributions – Final Boundaries for Victoria Released

(20 November – the tables in this post have been updated taking account of the final boundaries and incorporating split and merged SA1s. The complex way that final descriptions are released has made it difficult for me to update the transfers listed in the table but the margins have been updated.)

(Updated Friday 6 September with maps and more details on Chisholm, Deakin, Goldstein, Kooyong, Melbourne, Menzies and Wills. Estimated margins for Independent contests will be added later today..)

On Thursday 5 September the Redistribution Committee for Victoria released the fin al version of the state’s new Federal electoral boundaries. Draft boundaries were released in May and opened for public comment. This final version will be formally gazetted later this month and used for the first time at next year’s Federal election.

The redistribution has taken place to decrease the number of Victorian federal divisions from 39 to 38. The final boundaries have confirmed the abolition of the Labor seat of seat of Higgins in inner-eastern Melbourne.

Today’s release has included a string of minor adjustments to the draft boundaries, none of which appear significant to me. The release does not include the datafiles that permit new margins to be calculated. I won’t update the margins shown inside this post until the datafiles are released.

Re-calculating margins is a complex task of processing AEC polling place data files on where people voted in 2022 and comparing them with Bureau of Statistics files listing the low level SA1 (Statistical Area 1) composition of new electorates. Complicating the process is a re-numbering of many SA1s between the 2016 and 2021 Censuses. The 2022 AEC files used the old SA1 identifiers and the new electorate files use the new SA1 identifier. This has required a lot of fiddling with data to resolve inconsistencies between SA1 identifiers.

In my analysis of the draft boundaries in May I had to manually resolve these problems. I’ve managed to code the corrections this time though there are still a few inconsistencies that can’t be resolved by me. A number of the margins in this post have altered since May using the better correction method. The AEC will eventually release their own versions of new margins in the new year and they have a lot more resources than me to resolve SA1 inconsistencies and splits.

What this post does not yet do is take into account the adjustments in the final release of boundaries. I can’t do these calculations until the AEC release the maps and data files.

I have also not added estimated margins for a couple of Independent seats. That requires some manual re-calculations that I will do later today.

Change in Seat Numbers

Change in Seats Held by Party
ALP LIB NAT GRN IND Total
Old boundaries 24 8 3 1 3 39
New boundaries 24 7 3 1 3 38
With by-elections 25 6 3 1 3 38

Note: By-election line takes account of Labor winning Aston from the Liberal Party at an April 2023 by-election. Table does not take account of the decision by Monash MHR Russell Broadbent to resign from the Liberal Party and become an Independent.

Based on the two-party preferred results, including the underlying Labor-Coalition nature of Independent and Greens held seat, the changes in two-party preferred holdings are –

  • Old Boundaries 2PP: Labor 25, Coalition 14 (Liberal 11, National 3)
  • New Boundaries 2PP: Labor 25, Coalition 13 (Liberal 10, National 3)
  • Including by-elections: Labor 26, Coalition 12 (Liberal 9, National 3)

The main political implications of the changes are –

  • The Labor seat of Higgins is abolished.
  • Labor’s position in Wills is significantly weakened with the inclusion of strong Greens voting areas around Brunswick East, Carlton North and Fitzroy North. The Labor margin versus the Greens is reduced from 8.6% to an estimated 4.6%.
  • The transfer of strong Labor voting areas to Menzies, replaced by marginal Liberal country from Higgins and Kooyong, weakens Labor’s position in Chisholm, an estimated halving of the Labor margin from 6.4% to 3.2%.
  • The Liberal marginal seats of Deakin and Menzies in eastern Melbourne become even more marginal with Menzies flipping to become a notional Labor seat.
  • The strongest Liberal voting parts of Higgins have been transferred to Kooyong, held by Independent MP Dr Monique Ryan. Estimating support for an Independent in areas they did not contest at the last election, but my best estimate is that Ryan’s margin is reduced from 2.9% to 1.8%.
  • The boundary changes for Goldstein are estimated to increase the margin of Independent Zoe Daniel from 2.9% to 3.1%.

None of the estimates in this post take account of the changes announced with the release of the final boundaries. I do not believe that any of the final changes have much impact on marginal seats.

Seat tables can be found inside the post.Read More »2024 Federal Redistributions – Final Boundaries for Victoria Released