Kids from poor and middle-income families will be 'stuck at home' because of the soaring costs of days out and trips abroad.
A day out can cost around £80 and the charity is urging 'rip off' firms to stop unfair pricing and improve offers for families all year round.
Family Action Chief Executive Helen Dent said: "Families are facing summer on a shoestring with parents and children cooped up at home as a result of falling incomes and rising prices.
"We know that children get a boost from days out - including to their educational development.
"However, this year many parents are so worried that summer day trips will break the bank that they're cutting back."
Three-quarters of those polled said the biggest expense for a day out tended to be entry fees.
There were also concerns about the cost of transport and eating out.
One parent from Liverpool told the charity: "We looked about going away to do something and looked at the price but at the end of the week we didn't have any money. That's the problem."
Another parent said she could not afford to go anywhere because her children were not getting free school meals during the holidays and her food costs rose as a result.
Ms Dent added: "Whilst those in upper-income groups can still expect that a week's holiday in the UK forms part of a minimum standard of living, the vast majority of the families we support will be lucky to get out of their community for the day."
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