Published Monday, 23 January 2012
It is hoped the move with create more opportunities for improvement and repair works on the region's 8,200 historic sites.
Environment Minister Alex Attwood said it will come as a "significant boost" for owners.
"This is a real boost for our historic buildings," the SDLP minister said.
"They are a jewel in the crown of our tourism industry. The record numbers who passed through their doors during European Heritage Open Days is testament to that."
The current budget for grant aid is £3.246m.
Mr Attwood said it is important that listed buildings are protected, after a number of sites were damaged in fires over the past year.
He continued: "Obviously there are many demands on the public purse in Northern Ireland, but I want to do everything in my power to ensure that we preserve these historic buildings for present and future generations.
"Their tourism potential is great so it was good that I was able to secure some additional funding for this important grant-aid scheme."
The scheme will be administered by the Built Heritage Directorate of the Northern Ireland Environment Agency.