Parents in the South-east will be worst hit, with provision costing an average £87.75 a week, the most expensive places priced at £270 a week. The biggest annual increase is in the North-east where costs have risen by 19 per cent.
Daniela Reale, head of policy and campaigns for the Daycare Trust, which carried out the research, to be published tomorrow, said the cost of holiday childcare is now "completely out of reach" for many families.
Ms Reale said that one factor in the price rises was the lack of spaces in holiday play schemes. "When demand is high and supply is low, prices go up. Half of parents say they could not find enough schemes for the summer," she said.
David Kitson, 42, a legal aid solicitor from east London, said he and his partner, Hadley Long, 38, had struggled to find affordable childcare for their five-year-old daughter, Ella. "The best play scheme near here is £25 a day," said Mr Kitson, "and it is only open for four out of the six weeks' holiday.
"We book Ella in for two days a week and then take days off ourselves. We just cannot afford £125 a week for four weeks.
"We end up having to take two weeks' holiday at the end of August, and with all the odd days taken off to look after Ella I have almost used my holiday entitlement for the year. It is a very long break and the childcare provision just is not there," he said.
But the employers' organisation, the Confederation of British Industry (CBI), said employers are becoming increasingly flexible in "accommodating family plans" during the summer holidays.
More than half of parents use their savings or credit cards to fund summer childcare according to the high-street bank Abbey. It found that 42 per cent of working parents will arrange up to five family day trips, and a further 31 per cent will plan between six and 10.
Frances Walker of the Consumer Credit Counselling Service said: "Summer holidays will cost you more than you think they will, so parents do tend to use their credit cards more." Parents who look after their children themselves also face high costs.
Debit card Maestro found last month that parents spend an average of £59 a week on trips to museums, art galleries and theme parks, and an extra £29 on eating out and special meals at home.
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