Service providers operating across rural areas face inequitable costs compared to their urban counterparts for both adult and child social care, said the network.
Rural council taxpayers also faced unfair costs, warned the network in response to an inquiry by MPs who are examining the long-term future of adult social care.
RSN chief executive Graham Biggs said: “Social care is a national issue but it is in crisis.
He added: “While continuing to be delivered locally with flexibility for councils to respond to local circumstances and priorities, it should be 100% funded by central government to provide an adequate core service level for all residents nationally – irrespective of where people live.
“Council tax is an unsuitable taxation vehicle for demand responsive services and means rural residents face a postcode lottery when it comes to social care provision.”
Mr Biggs said council tax should only be used to fund social care if a given local authority decided extra money was needed to boost services above a core level locally.
It should not be used to fund the core, national, service, he added.
Mr Biggs said: “It costs substantially more to provide social care in rural areas than it does in larger towns and cities – and there is higher demand for services in rural areas.
“As a statutory duty, services have to be prioritised and other budgets – such as rural transport support, for example – are being cut significantly as a consequence.”
This was because older people make up a higher proportion of the population in rural areas than they do in urban areas, said Mr Biggs.
At the same time, the twin challenge of isolation and distance made it harder and more expensive to deliver services to dispersed rural populations.
Such costs inevitably and unfairly penalised rural councils – and were compounded by issues such as poor economies of scale and poorer external markets for delivery.
Mr Biggs said: “A future formulae to fund social care services must fully reflect the different costs of delivery imposed by both geography and population.”
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