Age Action said that it had a "productive" meeting with the Revenue Commissioners on the controversial issue of extra tax for pensioners.
Around 115,000 pensioners have received letters, informing them that they are liable for tax, following new communication between Revenue and the Department of Social Protection.
It has led to confusion among elderly people, some of whom are not liable at all.
Officials from Revenue will appear before an Oireachtas Committee on the matter this afternoon at 2pm.
Speaking after the meeting, Eamon Timmins of Age Action said that Revenue now accepts that it handled the issue badly.
"Certainly there is an acceptance from the Revenue that the way it was communicated added to the problem and they wouldn't be communicating in the same way if they had to do this exercise again," he said.