It suggests there are almost two million solo dwellers, and that eventually single-person households will take over, and the number of couples without children will take over from the number of nuclear families in Australia. By 2031 the Bureau estimates there will be 3.2 million single households. Yet, to date, singles have not been viewed as an important voting bloc, and compared to couples, face tax disadvantages. Firstly, those on single incomes are worst affected by bracket creep. That's where wage inflation places you in higher marginal tax brackets, thereby giving you less incentive to work more. Analysis by KPMG released last year – aimed at building the case for personal tax cuts ahead of the Abbott government's tax white paper - found that single-income households on $70,000 to $75,000 will be worst hit by bracket creep, facing a 60 per cent increase in income tax within a decade.

The KPMG report, Tax Reform For Our Future Success, said such households pay almost 20 per cent of their income in tax now. After 10 years, assuming a 3 per cent a year increase in income, they will move into the next tax-bracket and will pay about one-quarter of their income in tax, resulting in a 60 per cent increase from their current income tax levels. But this is not the only area where single-income people are disadvantaged, compared with couples. How financially better off people are, obviously, will depend on how much money they earn, how many weekly hours they work, if they have children(and how many). While singles don't have the stress of having a family budget to balance - and some still live at home well into their late twenties and thirties, eliminating the financial impost of rent and mortgages - there are no economies of scale in being single.

A couple can share the mortgage, grocery shopping and gas and electricity bills. For singles who do have a large mortgage - assuming they have been able to get into the housing market in the first place, that they live in their home alone, and pay the same interest rate as a couple with the same-sized mortgage – they are at disadvantage. PwC was asked whether singles with a mortgage are doing it tougher, took a profile of a single on $80,000 and a couple on $160,000. Both have a $400,000 mortgage at 5.10 per cent interest, and are average full time workers facing a marginal tax rate of 32.5 per cent. For the single, disposable income after tax and housing costs is $42,011. For a couple, it's $104,464.

As mentioned, this doesn't take into account the fact that families (especially those with kids) typically have a higher cost of living than singles. Or that one house may have higher maintenance cost than another house. Or that some people just can't manage their budget regardless of their marital status. But if most circumstances are the same, the couple benefits. And while both single and married couples structure their affairs to reduce their overall tax bill, there are some tax benefits only available to those who have tied the knot, by way of the "family trust". Rather than get taxed at the rate of the highest income earner in the family, income from any assets in the trust is distributed to family members (beneficiaries) with low tax rates. So effectively, the family can dodge tax, or pay very little of it.

Couples can also share their super. And then when they are old, take it out tax free. As long as they are under the age of 65 when sharing, the higher earning "spouse" (this includes de facto couples) can make a contribution into their non-working or lower-income-earning partner's super fund. So, if the partner earns less than $10,800, the spouse receives an 18 per cent tax offset in their tax return for a contribution of up to $3,000. This provides a maximum tax offset of $540 (although the tax benefit reduces and cuts out altogether once the partner's income reaches $13,800.) The tax treatment of super on death is also more favourable for couples compared to singles. Firstly, super benefits can remain in the system to support a surviving spouse. By preserving money in super, the spouse gets tax concessions on investments earnings.

Where super benefits are paid directly to a surviving spouse from the fund, those payments are generally tax free. In contrast, the super money of a single person must be paid out of a super fund on death and it is likely some tax will apply on transfer to that member's beneficiaries. Singles also face higher Medicare levy surcharges. Thresholds for the surcharge rate are a lot larger for families, presumably because the same level of income is being used to support both the earner and their dependent(s). Government policies, including those around taxation and housing, must be designed so that it doesn't ignore the needs of the nation's most disadvantaged. And quite often that is families on low incomes. But as we head into upcoming debates about population growth, housing, and tax reform, it's worth also remembering the lone person.