More than nine out of ten rental properties are priced beyond the reach of those on state supports.
A study by the Simon Community found that just 7 percent of properties available in 11 locations during August were priced at or below Rent Supplement or Housing Assistance Payments levels.
Single people fared particularly badly with just two properties affordable to them in total, but none in any of the five major city centres.
The Simon Community is reiterating the call of a number of homeless charities for the Rent Supplement limits to be increased and rent certainty introduced in Budget 2016.