DATEADD Method

When you say it's not working, do you mean there's a syntax error or does nothing (or the wrong date) get inserted into the Date column?

insert into Fixd_Inv values(1234,225,10,2,DATEADD(YYYY,3,'2013-04-10'))


I wrote this 
but not working

AFAIK, you can use expressions - not just simple values - in the VALUES(...) part of an INSERT command.

So you should therefore be able to use the DATEADD() function.