Unpaid care provided by friends and family for ill relatives is worth £4.4 billion every year in Northern Ireland, a lobby group has claimed.
More than 207,000 people in Northern Ireland are looking after people and providing care which would otherwise cost the state £18 a hour, said the study for Carers Northern Ireland.
The organisation said the Government must do more to support carers.
Director Helen Ferguson said: "With an ageing population, caring is becoming a fact of life for every family. Yet, whilst families are meeting this challenge, many are struggling with little or no help, or facing cuts to the care services and benefits they rely on.
"Unless we urgently rethink how our society supports carers, we will see increasing numbers pushed to breaking point - forced out of work and into poverty, ill-health and isolation."
The £4.4 billion cost was calculated by the University of Leeds.
The figure has risen by over a third since 2007. Carers' contributions exceed the total cost of the health and social care service in Northern Ireland. According to Carers Northern Ireland each carer saves the state on average more than £21,000 a year.
The organisation is calling for a review of the carer's allowance, protected funding for social care services, sustainable funding for the care system, as well as greater employer support in the workplace.
Ms Ferguson added: "Our society and public services could not function without the massive contribution made by Northern Ireland's unpaid carers.
"This contribution is something we can be proud of as a country, and demonstrates how strong our families and communities are."