Revenue have announced that if you file and pay your income tax for 2009 and preliminary tax for 2010 online by the 16th November 2010 you will not be liable to interest on penalties for late payment.  The usual deadline of 31st October applies to all other methods of filing and payment but as this falls on a Sunday all post received by 9.00am on Monday 1st November will be deemed to have been received on time.