Just a day before the final deadline, thousands of parents are waiting to see if they are eligible for free childcare.
Parents have been told they must apply by Thursday (August 31) for 30 free hours a week, but a technical hitch has left many not able to apply.
The government scheme, launched earlier this year, hopes to provide parents of three and four-year-olds with an additional 15 hours of free care a week.
Yet just hours before the deadline, thousands of parents are still waiting to sign up because of technical difficulties on the HM Revenue and Customs (HMRC) website.
The Department of Education said that more than 200,000 parents have already applied to join the childcare scheme, in which parents complete an online application.
Once the application has been completed a code is generated which can then be swapped for the free hours.
But these codes must by validated before a place can be guaranteed.
And only 56% have been approved so far, leaving around 82,000 people still yet to secure a place.
The scheme has been blasted by childcare providers, who argue there is a 20% shortfall between how much money local authorities are receiving to fund the scheme and the actual cost to nursuries.
This latest setback comes just a few days before the scheme is scheduled to launch on Friday (September 1).
Neil Leitch, chief executive of the nurseries' body the Pre-School Learning Alliance, said: "We have long warned that inadequate government funding rates would lead to a reluctance among childcare providers to offer many, if any, 30 hour places.
"Add to this the ongoing problems with the Childcare Service website, and it is clear that this is a policy coming apart at the seams."
HMRC has apologised to parents for the "inconvenience" but said that it has now made "significant" improvements based on customer feedback.
A HMRC spokesman said: "Those who apply in time and who get their code after August 31 will still be able to use it and the overwhelming majority – more than 200,000, have their codes already. Nobody need lose out as a result of the technical issues."
HMRC added that parents and providers experiencing difficulties or needing technical support can phone the childcare service helpline on 0300 123 4097.
Minister for Children and Families Robert Goodwill said that he is "determined" to make this scheme work and support as many families as possible with access to "high quality, affordable childcare".
He continued: "This is why we are investing a record £6 billion every year by 2020 in childcare – more than ever before – and doubling the free childcare available to working parents to 30 hours a week, saving them up to £5,000 a year per child."
However, Mr Leitch argued that for the "30 hours free childcare" to succeed the government must invest more.
"It simply must invest what is needed - both in terms of adequate funding rates and a robust IT infrastructure.
"If it doesn't, it is providers and parents who will be left short-changed."
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