The deadline for paying CGT arising on disposals made in the period from 1 December 2009 to 31 December 2009 is Sunday next, 31 January 2010.
Payment of CGT for disposals made in the period from 1 January 2009 to 30 November 2009 was due on or before 15 December 2009.
Details of disposals made during 2009 must be included on the 2009 Tax return.
Revenue's Capital Gains tax FAQ Guide is available here.