The Simon Community supported almost 8,300 people
The Simon Communities of Ireland say nearly 7,000 people will spend Christmas Day in emergency accommodation.
The group, which has published its annual report, has seen a 26% increase in people seeking support over a two year period.
The housing and homeless charity supported almost 8,300 people who are experiencing homelessness across the country.
Niamh Randall is national spokesperson for the Simon Communities in Ireland.
She said that 2016 had seen some improvements with people moving on to tenancies - yet the homelessness numbers continued to escalate.
"Today we are reporting the number of people we worked with increased to 8,300 people, this is an increase of more than a quarter in a two year period as the crisis intensified.
"Despite some movement out of homelessness the numbers in emergency accommodation continued to rise nationally to almost 7,000 men, women and children in 2016.
"These numbers represent someone's son or daughter, someone's sister or brother, someone's friend or neighbour, and the Simon Communities saw the devastating impact of this crisis each and every day this year across the country."
Among other findings from the report, it says 1,932 people were supported in housing all around the country, 1,030 people accessed emergency accommodation and 2,384 people accessed specialist treatment services.
Simon also says 911 people accessed education and training services, while 4,134 people accessed prevention and advice services.
More than 2,300 volunteers supported the work of their local Simon Community.
Ms Randall said: "Looking back on this year we saw the social housing waiting list grow to well over 100,000 households and ongoing pressure in the Private Rented Sector with quarterly data from DAFT.ie and the Residential Tenancies Board (RTB) demonstrating that rents increased at an alarming rate while the number of properties available decreased further.
"The launch of Rebuilding Ireland: Action Plan for Housing and Homelessness and the collaborative approach from the Cabinet, led by...Enda Kenny was significant, committing to ending the trauma of housing insecurity and homelessness for so many people across Ireland.
"This is the most comprehensive housing plan ever in the State.
For too long these areas have been dealt with separately, missing the point that they are intrinsically linked.
"2017 must herald more urgent action. Rapid implementation is required to keep pace with demand and to keep people in their homes thus stemming the flow of people into homelessness."
But she added: "There will be nearly 7,000 people spending Christmas Day trapped in emergency accommodation, many feeling hopeless and forgotten.
"Without shelter, safety and security it is almost impossible to function, to participate in society and to get involved in your community."