Section 19363 Of Article 1. Claim For Refund From California Revenue And Taxation Code >> Division 2. >> Part 10.2. >> Chapter 6. >> Article 1.

. Credits or refunds of overpayments of estimated tax shall be made by the Franchise Tax Board as provided in this article. Any amount paid as estimated tax for any taxable year shall be deemed to have been paid on the last day prescribed for filing the return for the taxable year (determined without regard to any extension of time for filing the return).