Play it conservative, and keep all your tax returns, along with insurance policies, pension-related and estate-planning documents (such as wills), forever. Keep cancelled checks, bank statements and receipts for at least three years, ideally seven – perhaps printing out copies if you receive them electronically. Do the same with any supporting documents for tax returns, such as 1099 and W-2 forms, charity receipts, bank and brokerage statements, and so on.
Hang on to stock trade confirmation receipts for as long as you own each stock and for at least three years (ideally seven) after you close out your position (usually by selling). Keep proof of improvements to property (such as a new roof) for at least three years after the sale of the property. Keep escrow closing documents (for both the purchase and sale of the property) for at least three years (again, ideally, seven) after the property is sold.
It’s smart to think twice before you throw out any documents related to your finances or major life events (such as a marriage or divorce). When you do dispose of such papers, be sure to shred them, to deter identity thieves.