Try this in C1:

=IF(B1="","",B1+28)

Format C1 as date. Actually, this doesn't test specifically for dates,
just for B1 being blank.

Hope this helps.

Pete

Mike wrote:
Can I set it up to where if there is a date in cell b1 then c1 is b1+28 (for
28 days)but if there is no date in b1 then c1 is blank? I can do the first
part but I don't know if the second part can be done. Thanks