One in 10 people employ domestic help to do cleaning, cooking or ironing, according to a new report.
Domestic staff include nannies, gardeners and butlers
The Work Foundation study said 74% of people said they did so because of lack of time, and 83% because they would rather be doing something else.
It said most of the estimated 2m nannies, gardeners, cleaners and butlers are employed on an informal, cash-in-hand basis.
It urged the government to do more to help people make more formal contracts.
The study found more than half of domestic staff were employed through word-of-mouth.
One quarter of carers and cleaners were paid below the minimum wage, according to the report.
Alexandra Jones of the Work Foundation said:
"Most domestic relationships are in the informal economy. Whilst this can work well for both sides, we are storing up longer term problems as this
"Those paid cash-in-hand for household tasks will not be
getting National Insurance payments, and are likely to be storing up pension
problems - particularly as they are predominantly women, who are already more
likely to be in poverty in retirement."
The group, which is an independent non-profit organisation, cautiously welcomed the government's recently announced tax breaks for households employing
But it said the breaks were unlikely to help very many households
because of the low qualifying threshold, and tended to exclude family members who took caring roles.
It urged the government to
raise the tax breaks and look again at how to recognise the enormous
contribution made by family members.
Ms Jones said: "We need to talk more about the hidden world of housework, as well as childcare and eldercare.
"Bringing these jobs into the public sphere, and recognising them as valuable contributions to the economy, should help tackle the stigma that remains attached to these crucial roles."
REASONS FOR HIRING HELP
Rather do other things - 83%
Have not got the time - 74%
An affordable perk - 70%
Housework 'waste of time' - 50%
Too tired for chores - 46%
Too big a job - 29%
Prevents arguments - 24%
One out of every five people asked said they could not cope with their domestic responsibilities.
This rose to one out of every three for those with children under the age of 16.
The report suggests wealthy households are more likely to have access to domestic help than lower income households.
Those with an income above £70,000 a year are 16 times more likely to employ domestic help than those earning less than £25,000.
While the biggest users of household help are those in full-time self-employment, 29% of whom employ someone to help with their chores.
The Work Foundation conducts research and consultancy work with companies and government departments aimed at improving the quality of working life.