Councils will experience a "surge of enquiries" as over 320,000 people contact them for assessments as the care cap is introduced, Partnership has warned.
The insurer estimates this significant number of people will start to contact their councils as the cap on care fees, set at £72,000, comes in on April 2016.
Currently, just 19% of people contact their local council for information if they are choosing a care home for themselves or a relative. Those in London (9%) far less likely to enquire than those in the West Midlands (30%.)
Partnership is anticipating not only will those currently looking for care will contact their councils but also the thousands of people who are already paying for their residential (155,696) or domiciliary care (168,701).
It has calculated that some councils will be hit harder than others due to the relatively high number of older people and large proportion of self-funders.
It is expecting around 36,484 people already in care to contact councils in the South East, where care home residents pay 55% for their care bills.
Earlier this year just 16% of self-funders in the region approached their local council. Similarly, councils in the South West will also face unprecedented pressure as 25,113 are likely to require information.
Chris Horlick, managing director of care at Partnership said: "With just under one in five people typically contacting their council for information on residential care, the introduction of the Care Cap is likely to lead to a significant increase in the number of consumers looking for information.
"And, not only will local government need to deal with people who are currently seeking assessment but also those who are already in care and wish to find out if they are eligible to start their care account ticking."
Horlick said the change will "place a significant burden on councils" as they struggle to manage the demands of their residents while also cutting their budgets.
He added: "It is vital that people recognise that while the Care Cap is a step forward, they will still need to pay a significant amount towards their care and getting regulated independent financial advice could help to make this process far easier."