Two-thirds of the highest-earning households surveyed by Ipsos Australia for MLC Wealth define themselves as "middle class" or "lower middle class" or "working class".

Each brings home at least $200,000, putting it near the top 10 per cent of households.

Yet, according to the survey to be released on Monday, only 2 per cent of the high earners define themselves as upper class and only 31 per cent as upper middle class.

Almost half (44 per cent), say they are middle class. A further 10 per cent say they are lower middle class, and 13 per cent working class.

Many households in the top 10 per cent struggle to save. The survey finds one in five live "pay cheque to pay cheque", spending everything they earn.

Two out of three say the cost of maintaining their mortgage is "having a big impact on their lifestyle".

"It's a paradox," says Lara Bourguignon, MLC's general manager of corporate superannuation. "The people who are earning more are also spending more and feeling left behind.

"It might be because they are living in the major cities, living in the expensive areas of major cities, or working so hard that conveniences such as eating out seem essential."

Asked to nominate the average income of a household that was genuinely upper class household, high income households nominated $454,000.

Middle earning households were more realistic, nominating $280,000.

Curiously, very low income households defined upper class in much the same way as high income households, nominating $549,000.

But low earning households were realistic about their own status. Four out of 10 described themselves as working class. None described themselves as upper class.

Ms Bourguignon said perceptions about what constituted a comfortable lifestyle were changing.

"It used to mean having access to a home, food, healthcare and schooling," she said. "Now it extends to overseas holidays, private schools and the latest technology. We have come to define comfortable as being able to do whatever we want. We have changed our perception of what normal is."

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