Could a 'mansion tax' help the housing crisis?

The suburb Bulimba has one of Brisbane's highest price tags. (Place Real Estate Agents)

The concept of a mansion tax — premium property owners paying additional tax — has been rolled out overseas to varying degrees of success.

Now, amid some of the most drastic proposed changes to Australia's tax system in decades and years of skyrocketing home values, one leading expert says it is an idea "worth considering".

Bulimba, nestled on the inner-city stretches of the Brisbane River, is a sought-after suburb with the property price tag to match.

With a median house price north of $2.3 million, residents in the leafy riverfront neighbourhood would likely have to cough up in the event a mansion tax is implemented.

Retiree Annette Wilkins does not support a mansion tax. (ABC News)

Retiree Annette Wilkins moved to the area four years ago and says she thinks the idea is "wrong".

"We're taxed enough, and then we get no benefits," she says.

Bulimba resident of 25 years Kasey Drake does not believe it would slow the growth of housing.

"The house prices keep growing because we have a growing population with needs," she says.

"A lot of young first home buyers need to get into the market."

"I think it's a great idea. If you live in a $5 million home, why not pay some tax?" he says.

There are two possible ways a mansion tax could be implemented, both of which have been seen overseas.

There might be a threshold, say $3 million, when additional tax is paid for every dollar above that amount when an owner sells a property.

That has been seen in Los Angeles while New York has done similar, but applying to buyers.

This property at Noosa Heads sold for more than $26 million in 2025. (Reed & Co)

The alternative works similarly to a land tax. Additional tax is paid annually on the unimproved value of a property over a certain threshold.

That option is due to be rolled out in the UK in 2028, with finance minister Rachel Reeves attempting to address intergenerational wealth inequality.

She described the policy in November as "asking those with the broadest shoulders to pay more".

It is not a concept completely foreign to Australia. The New South Wales Greens have previously floated an extreme wealth property tax, while Queensland Labor’s state conference endorsed a luxury homes levy last year.

Director of the Tax and Transfer Policy Institute at the Australian National University Robert Breunig is one of the country's leading tax minds.

"If you look at where the wealth is held in Australia, about 50 per cent of it is held in owner-occupied housing, that is, hous