All business records, especially sales and payroll must be kept for seven years. The Social Security Administration requires discrepancy be resolve anytime within this seven year window. The IRS and the states will audit within the seven year window. Keep all federal, state and local returns indefinitely and the all supporting documents for seven (7) years. Real Estate and stock market transactions records should be kept. Tax consequences of a transaction can depend on events that happened years earlier. Taxpayers often keep files in a single, easily accessible location. Consider keeping your files in a safe deposit box or other safe place outside your home.