TAX RECORDS: TO THROWAWAY OR TO KEEP . . . FOR HOW LONG

Contrary to popular opinion people don't usually get into trouble by not saving records but by saving the wrongs ones, outdated ones and too many, or not knowing where the right ones are. The huge stack of papers in the attic is often there due to inertia caused by not knowing which records need to be kept and which can be tossed.

Here's a quick guide.
RECORD RETENTION SIMPLY STATED:
• Keep tax returns (not records, but actual returns) forever.
• Keep every year-end summary of your pension forever

Keep everything else for 7 years from the last time it had any impact on your financial life.

Source: http://www.junewalkeronline.com/web/taxtips_09.html