How to handle kids who won't leave home

There are growing concerns about Australia's adult children living longer at home and eating into the retirement nest eggs of their ageing parents.

“To be staying at home in the mid to late twenties is a social norm now - there's no stigma with it, so we're seeing more of it,” Social Researcher Mark McCrindle said.

Half of all kids are still living at home in their early twenties and a few are still there in their late twenties.

One in a dozen still there at thirty, and sons are more likely to linger than daughters.

Twenty-something Ben is saving money by living at home, but his mother Leanne is spending more money.

“I moved back [home], I saved a few thousand dollars in the space of two months,” he said.

“You can see the bills change – whether it be water, electricity, gas, food – you've still got to supply for that extra person,” mum Leanne said.

“The impacts that it has on their parents are financial – it's slowly seeping some of the retirement savings their parents have,” McCrindle said.

On average, parents fork out around $5,000 per year keeping adult kids.

If that carries on into their mid-twenties, that amount can add up to the price of a new car.

If parents are happy to have adult kids, but they do not want to go broke, the answer could be a rental agreement.

Parents can negotiate a reasonable rent due on their adult kid’s pay day.

A small bond can be invested in an interest-earning account for a nice surprise when the kids leave.

A quarterly contribution to electricity and gas can also be considered, including rights and responsibilities such as a garage space in return for mowing the lawn.

“It took a little time for us to come into agreement but eventually, he pays a little bit of board and that's the way it is,” Leanne said.

“You do need to set some structures and some timeframes in place – and review it annually,” McCrindle said.