Most creche owners in a major providers' group claim they will have to close permanently without a cash boost from the State.
In a new survey, an overwhelming 87pc of members of the Federation of Early Childhood Providers said they will be unable to keep their businesses open without more government support.
Only 30pc said they had reopened since they were forced to close their doors due to the Covid-19 pandemic.
Of those that have opened, only 22pc are operating at full capacity, 27pc have reduced staff and 69pc said they were operating at a loss.
Ninety-one per cent of providers said emergency government supports were inadequate and 79pc feared for the survival of their business.
The federation represents more than 1,600 providers who care for nearly 55,000 children.
Its members' fears of closure come despite a €75m government package to support the sector that included the extension of a wage subsidy scheme and grants ranging from €1,000 to €10,000.
The federation's chairperson, Elaine Dunne, said another €150m is needed as the grants are not enough to cover operating costs.
"We are facing the total implosion of the sector unless the Government acts urgently," she said.
She added that the survey is "a dire omen for further waves of closures in the sector".
Former provider Gillian Powell, who ran the Haven Montessori in Bandon, Co Cork, said she closed permanently on June 29.
Five childcare services have closed in Cork, including two large services in the city.
"If that is replicated across the country in every county, we are looking at 150 services closing across Ireland," Ms Powell said.
"By allowing this to happen we are also affecting the ability of parents to go to work, for people to drive the economic engine of the State."
Just under a third of providers said they had reopened, although the numbers that normally operate during the summer months are generally lower.
This pessimistic outlook was revealed in a survey of 868 providers carried out earlier this month.
Seventy-eight per cent of those surveyed said they would prefer if the Department of Education, rather than the Department of Children and Youth Affairs, managed childcare.
A total of 93pc did not think there is enough support for children with additional needs, and 74pc felt these children were "regressing".
A spokesman for the Department of Children said 68 services had notified their closure to Tusla since the start of the year.
He said this was lower than last year, when 92 services indicated they would close between January and July.
However, Ms Dunne claimed many creche owners did not inform Tusla when closing their businesses.