Individuals should normally retain their tax records for three years, according to the IRS. This includes supporting documentation for income, deductions and credits. The three-year window reflects the period of limitations, which is when an individual can amend their return and the IRS can conduct an assessment for additional taxes.
The period of limitations ends three years after an individual files his tax return and two years after he completes the corresponding payments, explains the IRS. A taxpayer should maintain his records for seven years after claiming a loss from worthless securities or bad debt, six years after not reporting income that should be reported if it exceeds 25 percent of the amount indicated on his return, and indefinitely if he does not file a return.