Four of the worst performing authorities for care home quality are in Greater Manchester
Tameside, Manchester, Trafford and Stockport have the highest levels of care homes rated 'inadequate' or 'requiring improvement'.
A report has revealed the dramatic variation in the quality of care homes across the country - with four of the worst-performing authorities in Greater Manchester.
Figures compiled by older people's charity Independent Age show 28.2% are performing poorly in the North West, compared to 17.4% in London and the East of England.
Independent Age blamed low levels of funding from local authorities, poor pay and difficulties recruiting staff, as well as the lack of a good support mechanism for struggling homes to call upon.
Seven local authority areas had more than 40% of homes rated "inadequate'' or "requires improvement'': Tameside 56.8%, Portsmouth 46.5%, Kensington and Chelsea 45.5%, Manchester 43.8%, Bradford 43.6%, Stockport 43.3% and Trafford 43.1%.
While the overall percentage of homes receiving the Care Quality Commission's bottom two ratings fell compared to the previous year, every English region had at least one local authority where the proportion rose in 2017.
Independent Age chief executive Janet Morrison said: "Older people and their families are still facing an unenviable choice between poor care homes in some parts of the country.
"While it is encouraging that there has been an overall improvement in quality, this masks persistent variation in the quality of care homes within each region of the country. The market simply does not seem to be able to drive the rapid improvement needed in many areas.
"While the Government seems happy to deflect all decisions about social care into the vague promise of a green paper, local authorities are having to make difficult decisions now about care in their area. We urgently need both Government and local authorities to demonstrate that they understand the reasons for this variation and that they have the ability to address it.''
Dominic Carter, of the Alzheimer's Society, described the figures as "shocking and shameful'' and said the 70% of care home residents with dementia were "at the mercy of a system on the brink of collapse''.
"The Government must act now, with meaningful investment and a fresh approach to delivering care, or the system will collapse and people with dementia will continue to suffer needlessly,'' he said.
MP for Worsley and Eccles South, Barbara Keeley, who is also Labour's social care spokeswoman, said that ÂŁ6.3 billion had been taken out of adult care budgets since 2010:
"The unacceptable regional variation in the quality of care homes, which sees too many older people getting poor care, is the direct result of the Tories' devastating cuts to council budgets."
But a Department of Health and Social Care spokesman said: "Eighty-one per cent of care services are rated as good or outstanding, and we're committed to driving further improvements and reducing variation.
"That's why we're consulting soon on new measures to do just that, and have provided local authorities with an extra ÂŁ2 billion funding as well as a further ÂŁ150 million for next year."