The extra visit would have cost the council £26, a fraction of the cost of a hospital stay.
A man in his 90s in the north of England had his care allocation slashed by 92 per cent, leaving him with what his own carer described as “seriously insufficient” support.
More than 640,000 people in the UK rely on care in their homes, enabling them to stay independent.
“It is not a commodity to be purchased like paper clips,” the report remarks.
“Yet the findings in this report suggest that this is the direction of travel during a period of constrained public spending.”
Dr Ros Altmann, Director-General of Saga, said: “Care is not just about old people – it is about families and loved ones – and at the moment all of these people are being let down but our care system which is focused, not on people's needs, but on 'tasks' and 'visits' or 'hours' and 'minutes' of care.
“The fact that some visits are taking place in only 15 minutes is staggering – I doubt many people could get much done in their own home in only 15 minutes.
“Need for care is increasing and yet the amount being spent on care appears to be falling.”
But social services chiefs said the study highlighted the urgent need for a new model to pay for care for the elderly.
A Government White Paper is expected next week but is unlikely to include concrete plans for funding such as those set out last year in the landmark Dilnot Commission report.
Sarah Pickup, president of the Association of Directors of Adult Social Services, said: "From the care providers' point of view, it reflects the concerns we have had for some while now.
“It is very likely the care and support that people can buy with their personal budgets will do little more than directly meet their needs.
“And until a sustainable funding solution is found this is unlikely to change."