Revenue has taken more than 4,000 calls from the public about its voluntary disclosure initiative.
The initiative is for people who earned more than €635 in interest on deposits and investments undeclared for tax in 2005 or 2006.
They have until Monday to disclose their details.
After that financial institutions will have to hand over their personal information to the Revenue Commissioners. The information for 2007 has to be handed over next month.
Revenue will feed this information into its new computer system called Reap, and use it to vigorously pursue large tax defaulters who have not opted to make a voluntary disclosure about their deposits.
Over the past week alone, Revenue has received 700 calls from the public about the initiative, bringing the total number of calls since May to over 4,000.
Several hundred indications of voluntary disclosure have already been lodged with Revenue.
In addition more than €3m has been paid in settlement by just 55 people, despite the fact that payments related to the initiative are not due until January next year.
