TWENTY-THREE YEARS ago, a man in his 30s greeted the millennium “in despair. I’m a single parent, I live with my mother…I need a Life Plan.” Adrian Mole was fictitious: his bestselling comic diaries were a vessel for Sue Townsend’s anger at the inequalities and hypocrisies of late 20th- and early 21st-century Britain. But in the 2020s real Adrians are becoming more common.

The Office for National Statistics (ONS) says the census of England and Wales in March 2021 found 4.9m adult children living with their parents, up from 4.2m in the 2011 survey. Most people in their early 20s, and more than one in ten of those in their early 30s, are yet to fly the nest (see chart). And that doesn’t even count the Adrians: the tally includes only childless, single adults. Multi-family households (containing couples or lone parents under a shared roof) made up 1.4% of all households in 2021, up from 1.2% in 2011.

Granted, in some other countries grown-up children are even more reluctant to move out: two-thirds of young Italian adults live at home. But why are young Britons staying longer than they used to?

The ONS notes that there can be many reasons why adults live with their parents: those who do so are more likely to be unemployed, or to be students or carers, than those with places of their own. Judging by when the census was conducted, you might suppose that the covid-19 pandemic had caused more young adults to return home or to delay moving out. Possible, but not the whole story. Around 90% of adults living with their parents had done so for at least a year, the same as in 2011.

The likeliest explanation for more young adults staying put is that many of them cannot afford to buy or rent their own homes. In the first 20 years of the century, according to The Economist’s house-price index, British property prices almost doubled. According to Halifax, a lender, the average age of first-time buyers, which has been rising steadily for years, is now 32.

Not surprisingly London, which has the priciest housing (in 2021 the average rent swallowed 40% of renters’ gross incomes), also had the highest proportion of households with grown-up children, 26.8%. In the borough of Brent, in the north-west of the city, the share was almost one in three. The capital also recorded the fastest increase in the number of families with adult kids.

The squeeze on housing costs and living space is tightest in poor households. Not only are rents high, points out Molly Broome of the Resolution Foundation, a think-tank, but for many years the provision of social housing—for which many young people on low incomes would have been eligible in the past—has failed to keep up with demand. Local Housing Allowance (a rent subsidy), which was increased at the start of the pandemic in 2020, has been frozen since, while private rents have soared.

Lone parents were likelier than couples to have adult children at home. In London, more than half did. Homes with grown-up children are more likely to be officially classed as overcrowded—meaning, for example, that adults not in a couple, or more than two teenagers of the same sex, share a bedroom. In London almost one in four families with adult children was overcrowded, against just one in 15 in north-east England.

Since the census was taken, double-digit inflation, not to mention rising rents and mortgage rates, have added to young people’s incentive to stay in the parental home while they save what they can. They may—or may not—find comfort in what became of Adrian Mole. Townsend’s troubled diarist did eventually find a home of his own: a converted pigsty. His parents lived in another, next door. ■

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