 Access to care varies widely around the country |
Age Concern said government figures showed people in some areas of England are 160 times more likely to get continuing care than others.
The postcode lottery faced by those needing care was due to differences in local criteria for who was eligible.
But a national framework to be launched in October should increase access for thousands, the government said.
Continuing health care - where the NHS is responsible for, and fully funds care outside of hospital when a person no longer needs acute inpatient care - mainly affects very ill patients in nursing homes.
 |  There can be no justification for such huge variations in access to care  Gordon Lishman, Age Concern |
It is hoped the framework, unveiled in June, will standardise decisions on who is eligible, making the process faster, fairer and more simple to understand.
Age Concern welcomed the measures, which they estimated would increase the numbers of people receiving continuing care by about 7,000 - at a cost of £220 million.
But they warned around 60,000 people would still be missing out on the continuing care they are legally entitled to.
And they stressed that the framework would not cover social or personal care, which includes help with washing, feeding and dressing.
Care lottery
Figures obtained by the charity from the Department of Health show that the number of people receiving continuing care vary dramatically around the country.
In March this year Derby City PCT was giving just seven people continuing care, a rate of 0.26 people per 10,000.
By comparison, Harrow PCT was giving 826 people continuing care - a rate of 41.75 per 10,000 people.
This is despite Harrow having 75,000 fewer people and a younger population.
Gordon Lishman, director general of Age Concern, said they were fearful that the new framework alone would not result in the cultural change in PCTs needed to reduce the variation.
"These new figures beggar belief.
"Individuals face a postcode lottery in getting NHS continuing care.
"There can be no justification for such huge variations in access to care."
He said the framework needed to be monitored carefully to assess its impact in stamping out the "unfair practice".
Care services Minister, Ivan Lewis said: "We are aware of the variation which is exactly why we published the National Framework for NHS Continuing Healthcare only two weeks ago.
"The new framework will help ensure that all the people who are eligible for NHS Continuing Healthcare or NHS-funded nursing care will receive the care they need."
He added they would be monitoring the situation closely to make sure that individuals are not missing out.
Andrew Chidgey, head of policy and campaigns at the Alzheimer's Society said: "Many people with dementia struggle to get NHS continuing care funding because the system is confusing, complicated and unfair.
"It is vital that we establish a more transparent and equitable system, which provides the best possible care for people with dementia, and hope this will become a reality in the near future."
