How long should I keep my tax information?
The Franchise Tax Board (FTB) may request information from you regarding your California income tax return within the California statute of limitations period, which is usually the later of four years from the due date of the return or the date the return is filed. (Exception: an extended statute of limitations period may apply for California or federal tax returns that are related to or subject to a federal audit).
Keep a copy of your return and the records that verify the income, deductions, adjustments, or credits reported on your return. Some records should be kept longer. For example, keep property records as long as they are needed to figure the basis of the property.