Elderly people who pay £8,000 to join the Conservatives’ proposed residential care scheme may still have to pay annual top-ups, The Times has learnt. Andrew Lansley, the Shadow Health Secretary, called the scheme “a guarantee that absolutely all fees for permanent residential care would be waived for life”.

However, the party acknowledged yesterday that it would set a ceiling on the benefits, meaning that an unknown number of elderly people would have to pay more to cover their fees.

Mr Lansley’s spokesman said that it would be unreasonable for the Tories to be expected to fund accommodation in luxury homes costing more than £40,000 a year, and in such cases it would be reasonable to ask for a top-up.

However, The Times has learnt that the maximum, which is currently the subject of a consultation by the Conservatives, could be dramatically lower.

Insurance industry sources said yesterday that the Tories had told them that the voucher would be worth the average cost of care — £26,000.

Mr Lansley rejected this, and insisted that his modelling had suggested that he could meet the costs of everyone in care homes funded by local authorities. His spokesman conceded, however, that the ceiling — which the party says will be based on the “highest average rate” — has yet to be set.

Mr Lansley’s advisers also conceded that the insurance industry would play a large part in determining the figure, since the scheme would not work without its co-operation. Insurers could attempt to drive down costs to make the scheme as profitable as possible for them.

Niall Dixon, the chief executive of the King’s Fund, the health and social care think-tank, also said that he had seen documents suggesting that the voucher would amount to £52,000 over two years, which could mean half of all care homes having to charge additional fees.

He said that the plan was a welcome contribution to the fraught issue of spiralling social care costs, but warned that the Conservatives must be transparent about the way that it would be funded.

“We have raised right from the outset that in places like Essex a voucher might not pay for all your care. However, the topping-up cost would be a lot less than the full cost of the care, so I wouldn’t get worked up about this.”

He also warned that the scheme may provide a perverse incentive for people to go into a residential care home when it was not needed.

An insurance industry source said: “They told us that they would offer a voucher for annual average cost. But we want this scheme to work. So as long as they work with the industry we are happy.”

The Conservatives have said that one in five people ends up in residential care, but the source said that their figures suggested this was a deliberate overestimate to give the scheme more room for error.

The Tories say that their modelling, by an actuarial company, suggests that they would be able to pay for everyone in local authority care. Those worried about top-ups would always be able to find somewhere cheaper, they added.

A Conservative spokesman said: “We have modelled the scheme to pay out all the fees of someone entering a registered care home, including the highest average costs in more expensive areas like London.

“Obviously, for people who want to stay in very expensive, luxury care homes there will have to be a point at which people need to pay additional top-up costs.”

Mr Lansley told the party conference in Manchester that slashing NHS red tape could free up £4 billion over four years to pay for frontline health services.

Spiralling running costs of primary care trusts, the £1.94 billion-a-year cost of health-related quangos and the bills for Whitehall and strategic health authority operations would all face the squeeze.

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