A third of local authority houses are in mortgage arrears, with a massive one in four behind on their payments by over six months, new figures reveal.
And almost half of those who have loans for houses in shared ownership – where people on lower incomes share the cost of a home with local authorities – are also behind on their mortgages.
The figures, obtained by Labour TD Kevin Humphreys, also show a spiralling number of evictions by local authorities.
They are the first detailed compilation of mortgage arrears for local authority housing.
Out of a total of 20,277 local authority houses in mortgage arrears, 6,275 (31pc) are more than three months behind, of which 4,968 (25pc) are over 180 days behind on their payments.
The Department of the Environment does not hold data for loans which are more than a year in arrears.
Although Dublin City Council, because of its large population, has the highest level of arrears, smaller counties like Kildare, Westmeath and Laois also recorded relatively high figures. Some of the lowest figures were in Leitrim, Limerick County Council and City Council and Cork City Council.
Mr Humphreys, who obtained the details through a parliamentary question, said the figures were "very concerning". "There's obviously great stress on people who have local authority mortgages and people on shared ownerships," the Dublin South-East TD said.
He said it was creating a huge financial problem for the councils, as well as putting many homeowners under strain.
"There has been a concentration on the mortgages held with the financial institutions but there has been no look in a sympathetic manner at those people who have local authority mortgages to take them out of the anxiety they have been suffering."
Environment Minister Phil Hogan said councils "have long provided housing loans to less affluent members of society".
He also said his department had issued guidelines to councils based upon the Central Bank's code of conduct for private banks dealing with distressed mortgage holders.
The guidelines include allowing options like mortgage to rent, in cases where the mortgage is regarded as unsustainable. This scheme allows people switch from owning their home to renting it.
The figures also show that the number of home repossessions by councils has increased sharply in the past three years, with a total of 89 in 2010, 103 in 2011 and 137 last year.
While this includes both voluntary repossessions and evictions, there has also been a large increase in the number of evictions. In 2010, only 18pc of repossessions were evictions, rising to 52pc in 2011 and 53pc last year.
The highest number of evictions last year was in Dublin City Council, with 31. In contrast, numerous councils – such as Cork City – had no evictions at all.
Junior Housing Minister Jan O'Sullivan said: "In all circumstances, local authorities explore every option to avoid repossessions and it is very much a last resort."