The Irish Mortgage Holders Organisation is strongly criticising the decision to hit another 100,000 households with property tax bills.
Homes built since 2013 have been exempt to date, but the government says the charge will apply to them from November.
The first bills will arrive early next year.
David Hall, from the Irish Mortgage Holders Organisation, says it's a bizarre decision.
"It's the wrong call at this time, when many people have health priorities and financial priorities following on from the pandemic.
"The numbers are absolutely clear, so many hundreds of thousands of people are still affected by the pandemic, still have their employment affected, still requiring government supports.
"To hit them with a further tax during such uncertainty is crazy."
