REVENUE Commissioners chair Josephine Feehily said that Revenue had made a mistake in not sending enough information to people about paying their property tax for 2014.
She said this was the reason it had pared back the letter sent to 960,000 households, believing that they had sufficient information from the booklet sent out earlier this year for the payment of the 2013 property tax.
"Clearly this was a mistaken assumption on our part," she said.
She was appearing at the Oireachtas Finance committee to deal with the fallout from the decision to require homeowners to pay their property tax for next year before Christmas if they were using a credit or debit card.
Ms Feehily said that all of the payment options for the property tax had been successfully used before.
She said that the Revenue had to ask people to file their property tax return this month for 2014 so that it could provide seven different payment options. She said that returns had already been made for 205,000 properties, giving a compliance rate of 35pc with three weeks to go to the filing deadline for 2014. She said people had five payment options if they did not want to pay their property tax for 2014 this year.
Ms Feehily defended the decision to require the immediate payment of the property tax by credit card. She said that one of the Revenue's responsibilities was to take steps to reduce opportunity for non-payment.
"I would never refuse to consider changing things for next year. I just think its important not to think this is simple," she said.
Ms Feehily said it was risky to allow people to delay their credit card payment until January 1 - saying that meant people would have to be paying on New Year's Eve or New Year's Day.
Labour TD Ciaran Lynch, who is chair of the committee, told Ms Feehily that it was possible for credit card payments to be taken at a later date in hotel bookings and M50 toll charges.
"We are talking about a systems issue as opposed to a legislative issue," he said.
But Ms Feehily responded strongly by asking him if taxpayers would be happy giving their credit card details to the Revenue to dip into when it liked.
Ms Feehily confirmed that people could send a post-dated cheque to the Revenue so that their property tax payment would not be cashed until January 1.
But she said that it was a riskier method of payment because people did not always put their property tax ID number on the back of the cheque. She said there were still cheques from earlier in the year that could not be matched to a property by the Revenue.
"Please put identification on the back of it," she said.