I am moving from ProSeries to ProConnect so I need to back up my older clients as a PDF. How long do I have to keep my clients files if they're no longer a client?

[abctax55]

Depends on the State.  

I keep seven years (from date of filing, including extensions).  YMMV

[IRonMaN]

I also keep 7 years.  I don't recall the reason why I picked 7, but maybe it was just because 7 is a lucky number.

[abctax55]

As opposed to 'one is the loneliest number' 😉

I do seven because of CA requirements (of course, CA is a P.I.T.A.)