try this

=NOT(OR(MONTH(TODAY())-MONTH(A2)<=3,MONTH(TODAY())-MONTH(A2)<=6))

On Dec 2, 6:51*am, Loadmaster
wrote:
I want to format cell A1 to turn red if the date in cell A1 is not within the
current or previous quarter date specified in cell B2 with:
=DATE(YEAR(TODAY()),INDEX({3;6;9;12},INT((MONTH(TO DAY())+2)/3))+1,0)