Some 55% of parents charge their grown-up children rent, according to a recent poll on Moneywise.co.uk.
Over two fifths (41%) of them do so because the sooner they learn to provide for themselves, the better.
The other 14% charge rent simply because they can't otherwise afford to cover all their bills.
However, with the typical mortgage size for first-time buyers in England and Wales hitting £212,000 during the three months to the end of June - according to the Council of Mortgage Lenders - it's not surprising that 44% of Moneywise readers allow their grown-up children to live at home rent-free.
Some 17% put this down to the fact that they'll do everything they can to help their children save for somewhere of their own. The other 27% just accepted the financial hit as part of being a parent.
The Moneywise.co.uk poll, voted for by 2,419 people, indicates that parents are torn between trying to help their children at the same as coping with increasing household costs.
Last year, more than 3.3 million young adults between the ages of 20 and 34 were living with their parents - up 26% from 1996, the Office for National Statistics reported.
On average, stay-at-home 'kidults' cost their parents almost £850 a year in added household bills, according to research by VoucherCodes.co.uk.
Mumsnet editor Sarah Crown recently told Moneywise: "From university tuition fees to rising house prices, the financial pressures on young people today are intense and, as a result, many more are finding themselves living at home for longer."
However, she added: "Mumsnet users broadly agree that if grown-up children to ask to stay with their parents while they're getting on their feet, charging them a small amount of rent, based on their income, is a sensible idea; it helps move the relationship on to a more equal footing – and, of course as adults, they should expect to contribute to household expenses."