InfoPath:

[Mrs. Cooper]

In Excel, a simple sum formula can add days to a date. For example: if cell
A2 has a date and in cell A3 I enter =A2+30 the formula will return a date
that is 30 days out from the date is cell A2
How can I add days to a date in Infopath?

 

[S.Y.M. Wong-A-Ton]

You'll have to use the new addDays function in InfoPath 2007 or write code to
do the same in InfoPath 2003.