Only 6% of properties are available within Rent Supplement (RS) and Housing Assistance Payment (HAP) levels, according to a study by the Simon Community.
The 'Locked Out of the Market' snapshot study says that there were 561 properties with no income limits available to rent across the 11 locations researched in August, but just 34 properties were available within RS/HAP.
The organisation said increases in RS/HAP limits introduced in July 2016 are no longer effective.
In its pre-budget submission, the Simon Community also wants the Government to make the provision of affordable housing a priority, and to use Budget 2019 to ensure people are prevented from losing their homes.
Simon National Spokesperson Niamh Randall said the snapshot study conducted over three days in August was indicative and showed the pressure people were under.
Speaking on RTÉ's Morning Ireland, Ms Randall this is the 12th study of its kind and the situation has deteriorated since RS/HAP limits were increased in 2016.
The study looked at the number of properties available to rent on property website Daft.ie over a three day period and examined what properties were being advertised at and compared them to RS/HAP limits.
Ms Randall said the study provides a snapshot of the lived experience for a person or a family looking for a place to live.
The study showed that there were 18 properties available for a single parent or a couple with one child and nine of those only had one bedroom, raising issues of suitability.
Ms Randall said the the rental market has seen a significant constriction since 2012 and people are under huge pressure, but particularly those on low incomes or who qualify for RS/HAP.
She noted that the Department of Social Protection and Department of Housing can increase the limit but this is done on a case-by-case basis and is not a long-term solution to the situation.
She said there is huge pressure in urban areas, and now that is spreading to the commuter areas.
"Anything that can be done to speed up the process without compromising on quality is a good thing."
Minister for Housing Eoghan Murphy has said that the Government must be "very careful" about making changes to tax, when asked about introducing a tax rebate for renters.
He said that "in the long term could do more damage, even if it is responding to a short term need".
The minister added that it was "one of the mistakes made in boom years".
He described HAP as "not a perfect response", but said that it will be used until enough new homes have been built, so that people can be supported in rented accommodation.
There are more than 45,000 HAP tenancies.
