Australia has one of the most discriminatory tax systems against single income families in the world.

A single income household with an income of $120,000 pays $10,000 more tax in Australia than a double income family with the same joint income of $120,000.

To put it another way: a double income family could potentially earn up to $215,000 a year before they pay the same average tax rate as a single-income family on just $120,000.

This is unfair. People with similar ways and means should pay similar amounts of tax. 

A recent OECD report found that, of the 37 countries examined, Australia had the 5th most discriminatory tax system against single-income families behind Finland, Ireland, Mexico and New Zealand.