California Revenue & Taxation Code
Cal. Rev. & Tax. Code § 18566
Official textleginfo.legislature.ca.govlast amended
Returns filed under this article on the basis of the calendar year shall be filed on or before the 15th day of April following the close of the calendar year. Returns made on the basis of a fiscal year shall be filed on or before the fifteenth day of the fourth month following the close of the fiscal year.
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