California Statute of Limitations

Original tax return was filed on or before April 15th : If you are making a claim for refund, file an amended tax return within four years from the original due date of the tax return or within one year from the date of overpayment, whichever period expires later.

Original tax return was filed within the extension period (April 15th – October 15th) : If you are making a claim for refund, file an amended tax return within four years from the date the original tax return was filed or within one year from the date of overpayment, whichever period expires later.

Original tax return was filed after October 15th : If you are making a claim for refund, file an amended tax return within four years from the original due date of the tax return (April 15th) or within one year from the date of overpayment, whichever period expires later.

If you are filing your amended tax return after the normal statute of limitation period (four years after the due date of the original tax return), attach a statement explaining why the normal statute of limitations does not apply.

If you are filing your amended return in response to a billing notice you received , you will continue to receive billing notices until your amended tax return is accepted. You may file an informal claim for refund even though the full amount due including tax, penalty, and interest has not yet been paid. After the full amount due has been paid, you have the right to appeal to the Office of Tax Appeals at ota.ca.gov or to file suit in court if your claim for refund is disallowed.

To file an informal claim for refund, check box l for “Informal claim” on Schedule X, Part II, line 1 and mail the claim to: