How do I contact California state taxes customer service?

For California state tax refund assistance, contact the Franchise Tax Board (FTB) at 800-852-5711 (weekdays, 8 AM - 5 PM) or use the 24/7 automated line at 800-338-0505. You can also check your refund status through MyFTB chat or online. For specific issues, you may need to write to the FTB or contact a taxpayer advocate.