Parents will be forced to shell out more than £100 a week to keep a child occupied and cared for during the six-week summer holidays, according to new research.
It suggests that holiday childcare is becoming increasingly expensive, with families facing differences in cost depending on where they live.
The study also suggests that around one in six mums and dads had to call in sick last year in order to look after their children during the summer break, whilst others say they were forced to give up jobs due to lack of childcare.
The Family and Childcare Trust's annual holiday childcare report found that in Britain, the average cost of one week's full time (50 hours) holiday childcare - including holiday clubs and play schemes - now stands at £114.51.
Overall, the cost of holiday care is around 1.7% more expensive than last year, the survey says.
It adds that prices have fallen by 3.1% in the maintained sector - childcare run by local councils and other public sector bodies - and risen by 2.7% in the private sector, including private clubs and play schemes.
The study is based on data collected from local authorities.
The findings show that in England alone, full-time holiday childcare costs around £116.18 a week on average.
Prices are the highest in the South East, with a weekly cost of £140.88 on average, whilst families in the North West have the lowest average weekly holiday childcare costs at £103.38.
In Wales holiday childcare costs £109.66 on average, and in Scotland it is £104.28.
A survey of parents conducted by parenting website Netmums and the Trust found that around 17% said that they had to take days off work sick last year to cover childcare.
This represents almost a million working days lost, the Trust said, which it claims costs the economy almost £100 million each year.
One in four of the mums and dads questioned said that they had been forced to cut their working hours during the school holidays, and one in eight (12%) said they had given up jobs because they could not find childcare.
More than a third (35%) said it was difficult to find care they could afford, and two thirds (66%) said that the summer is the most difficult time of year for finding childcare.
Trust chief executive Anand Shukla, said: "A combination of unaffordable prices, lack of holiday childcare and inflexible employers is not only causing stress for parents, but it's bad for the economy.
"Most parents have no choice but to work, and should not have to take sick days to manage childcare. This is not the way to operate a modern economy, and this is why we are calling on employers and head teachers to help parents manage the school holidays, and on government for a new childcare strategy that properly represents the realities working families face today."
:: The survey, conducted by Netmums, questioned 1,587 parents in May.
Shadow childcare minister Lucy Powell said: "Under David Cameron childcare costs are soaring and the availability of childcare is plummeting, causing a summer of misery for many parents trying to balance work and family life in the holidays.
"But while families facing a cost-of-living crisis come under more and more pressure, this Government has no plan to support families struggling with their childcare before the next election."
Government research published last month showed that just under a fifth (19%) of primary schools offered families care during the holidays.
Schools in richer areas were more likely to provide childcare out of term time than those in poorer areas.
An analysis of published figures carried out by the 4Children charity concluded that there are around 450,000 places in holiday clubs or with childminders available to the around 6.8 million youngsters in England aged between four and 14.
This is equivalent to one place for every 15 children, the charity said.
A Department for Education spokesman said: "We understand that childcare is a key issue for parents over the holidays. That is why we want to improve the choice, quality and flexibility of childcare provision in England.
"After 12 years of consistently rising prices, costs in England have stabilised for the first time - in fact once inflation is taken into account costs for the majority have actually fallen.
"All three and four-year-olds get 570 hours of free childcare a year. We have introduced tax free childcare for almost two million families so working parents with children under 12 can save up to £2,000 per child per year from 2015. This will help to ensure parents can have what they want - affordable and accessible childcare."