Fewer households in Slough applied to provide foster care last year than before the pandemic, new figures show.
It comes as the number of foster care places across the England continued to decrease.
A charity said services are under 'immense pressure' and called on the Government to take "urgent action" to recruit and retain more foster carers.
This comes after the Government announced a £44 million package to support kinship and foster carers in the Autumn Budget, which includes improving local authorities' access to regional fostering recruitment hubs.
Ofsted data shows local authorities and independent fostering agencies across the country received 8,500 applications from prospective fostering households in the year to March, up from around 8,000 the previous year.
In Slough, five households applied to the local authority to provide foster care in the same period, down from 10 before the pandemic.
Across England, the total number of approved foster care places managed by local authorities has fallen to the lowest level in five years, with 18,860 households providing 37,430 places as of March.
In Slough, there were 55 local authority-managed foster households, including 10 newly-approved ones.
Figures are rounded to the nearest five, while further households in the area may have applied and been approved through independent fostering agencies.
Sarah Thomas, chief executive of The Fostering Network, said the figures highlight "the immense pressure foster care is under", warning this will have "a detrimental impact on children and families".
"The fewer foster carers we have, the more children who may end up in residential care or in homes away from their families and friends," she added.
"Action needs to be taken to make fostering more sustainable – we urgently need a UK-wide fostering strategy that addresses the retention of foster carers as much as recruitment."
Colette Ferns, head of Fostering and Adoption England and Scotland at Action for Children, said England's broken care system is failing to deliver stable and loving homes.
She added the cost-of-living crisis often prevents prospective households from fostering as the costs associated with caring for a child can be a major barrier.
Ms Ferns urged the Government to take swift action and increase the availability of foster care families and children’s homes and ensure the national fostering allowance covers the care costs.
Nationally, 28,165 enquiries were made to local authority services, though just 3,020 applications were submitted.
In Slough, 20 households enquired about fostering between April and March.
Yvette Stanley, Ofsted’s national director for social care, said: "It’s a big concern that the number of fostering families continues to fall."
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here