Complaints to the local government ombudsman about adult social care in England have more than doubled over the last four years, it has been revealed.
Local government ombudsman Jane Martin said the body received 2,456 complaints and inquiries about adult social care last year, a 13.8% increase since 2012 and a 130% leap compared with 2009.
The majority of complaints, at 86%, were about local authority delivered services while relatively low numbers of complaints were received about private providers, at 218, or 9% of the total.
The complaints included 442 about assessment and care planning, 429 about fees, grants and payments and 406 about residential care.
The local government ombudsman (LGO) resolves individual complaints where people are dissatisfied with the response they have received either from a private care provider or a council.
"All local authorities should review the data on complaints to consider the quality of care and effectiveness of complaint handling in their area," the report said.
"Those scrutinising services need to look at the details behind the numbers.
"Sometimes higher numbers of complaints reflect organisations with an open and mature approach to the concerns of their service users, where feedback is encouraged and actively sought out. Similarly, lower numbers of complaints can indicate that there needs to be a focus upon the accessibility of the complaints process."
The LGO said the 2,456 complaints and inquiries about adult social care amounted to a "small" number in the context of 1.3 million adult social care users. It said 46% of complaints received were upheld.
Anna Bradley, chairwoman of Healthwatch England, said: " It may seem counterintuitive but we should look on the increasing number of complaints as a good thing. It means that more people feel able to make their voices heard when the standard of care they receive from their carer or care home isn't up to scratch.
"Providers of social care services, whether they be local authorities or private companies, need to learn to see complaints as a vital source of information to help them improve and ensure others don't have to suffer the same poor standards in future."
Andrea Sutcliffe, chief inspector of adult social care at the Care Quality Commission (CQC), said: " I welcome today's report which demonstrates how important it is for adult social care services to respond positively to the concerns that may be raised by people using these services or their family and friends.
"When we look at whether services are safe, caring, effective, responsive and well led we will be considering how well complaints are handled and acted upon. This will help to inform our judgment of whether services are outstanding, good, require improvement or inadequate."
A spokesman for the Local Government Association (LGA) said: " Huge efforts have been made by councils to ensure people in care have their voices heard.
"Local government is one of the most trusted parts of the public sector and a rise in complaints can be an indication that local authorities are making it easier for those in care to give feedback, and that people are confident that their council will act on it."
A Department of Health spokeswoman said: "Our care services must listen when people raise concerns and take swift action to stamp out poor care.
"We are working to join up the health and social care complaints systems so that issues are dealt with by the right organisation as quickly as possible, and bringing in tougher rules so that staff, at all levels, and the organisation itself are properly held to account.
"We are making it easier for the CQC to prosecute when serious failings occur and we are also introducing a fit and proper persons test for board members of organisations."