In Australia, each federal electorate has about 120,000 voters on average, though the actual number varies from seat to seat and can change after redistributions.
What an electorate is
An electorate, also called a division, is the geographic area represented by one member of the House of Representatives. The House has 150 members, so there are 150 federal electorates across Australia.
Why the number is not exact
Electorates are drawn around population and enrolment, not fixed headcounts. That means some seats have more enrolled voters than others, especially when comparing inner-city areas with fast-growing outer suburbs or large rural divisions.
The official average often gets rounded in public material, and you may see figures around 112,000 to 120,000 voters depending on the source and timing. The difference comes from whether the source is referring to enrolled voters, residents, or an average based on a particular redistribution period.
A practical way to think about it
If you want a simple answer, use this: a typical Australian federal electorate has roughly 120,000 people on the roll, but the real number can be higher or lower in any individual seat. Some electorates are much larger geographically, but that does not mean they have more voters; rural seats can cover huge areas with comparatively fewer people.
How many electorates there are
Australia currently has 150 House of Representatives electorates, with the number divided across the states and territories according to representation entitlements. The current breakdown is 46 in New South Wales, 38 in Victoria, 30 in Queensland, 16 in Western Australia, 10 in South Australia, 5 in Tasmania, 3 in the ACT and 2 in the Northern Territory.
In short, there is no single exact figure for every electorate, but “about 120,000 voters each” is the best general answer.