The average family will be spending two fifths of their disposable income on childcare in 10 years time, a charity has claimed.
Childcare is one of the biggest challenges for parents, with many prevented from returning to work, or working enough hours because the cost of paying a nursery or childminder is too expensive, 4Children said.
It called for a new guarantee of quality, affordable childcare for every family with children aged up to 14 that needs it.
The charity said it had analysed existing data and research and concluded that under current figures, by 2024 around 40% of an average family's disposable income will be taken up by childcare costs.
And in 50 years time, all of a family's disposable income would be spent on childcare.
Currently, just under a third (31%) of a family's disposable income is spent in this way, it adds.
In a new report, the charity said: " A guarantee of childcare needs to be affordable as the high cost of childcare is currently prohibitive to many families. Over the next 10 years Government should extend its investment in childcare to ensure that the cost to parents becomes affordable.
"For pre-school childcare the first 25 hours of childcare would be free with parents paying for additional hours. Schools have the potential to provide childcare as part of the extended school day at a lower cost and additional investment from Government is needed to ensure this happens."
4Children said it was urging the Government to extend the pupils premium - extra cash for poorer pupils which follows them from school to school - to pre-school children in next week's Budget.
It also suggests that working parents who receive tax credits or Universal Credit should have 85% of their childcare costs met by the state.
The report calls for all families to have access to affordable, high quality childcare from the end of parental leave until a child starts school, with a guarantee of 8am to 6pm care for four to 14-year-olds in and around schools, including during the holidays.
4Children Chief Executive Anne Longfield, said: "Childcare is one of the biggest challenges for parents today who are making tough decisions between children, family and work. Too many parents are still prevented from returning to work or working the hours they need because childcare is too expensive.
"Although we are pleased that all the main political parties have committed to incremental improvements in childcare they all fall short of the radical shift needed to make childcare available and affordable for all families. More ambition is needed to deliver a guarantee of childcare to meet the needs of the modern workforce over the next 10 years.
"As an immediate step to begin to help deliver the changes needed, 4Children is calling on the Chancellor to commit in his budget next week to extend the pupil premium from schools to the early years to benefit some of the most disadvantaged children by increasing support into childcare provision."
A Government spokeswoman said the cost of childcare in England had fallen last month for the first time in 12 years.
She said : "This means more parents are able to access affordable childcare and support their families. This is in contrast to rising costs in Scotland and Wales, highlighting the difference this Government's reforms are making."
The government is meeting up to 70 per cent of childcare costs for low- and middle-income families through tax credits, the spokeswoman added.