California Tax Deadlines
State income tax filing deadlines, extensions, and estimates for 2026.
California Franchise Tax Board
https://www.ftb.ca.gov
individual deadline
Due: Apr 15, 2026
Extension: Oct 15, 2026
Form: Form 540 / 540NR
Automatic extension to file; payment due by April 15.
Estimated Payments
Sole Proprietorship deadline
Due: Apr 15, 2026
Extension: Oct 15, 2026
Form: Form 540 / 540NR
Sole proprietors file with personal return; automatic extension to file.
Estimated Payments
Partnership deadline
Due: Mar 16, 2026
Extension: Oct 15, 2026
Form: Form 565
Automatic extension for CA partnerships; payment still due by original date.
S Corporation deadline
Due: Mar 16, 2026
Extension: Sep 15, 2026
Form: Form 100S
Automatic extension for CA S corporations.
C Corporation deadline
Due: Apr 15, 2026
Extension: Nov 15, 2026
Form: Form 100
Automatic 7-month extension for most corporations in CA.
Estimated Payments
LLC deadline
Due: Mar 16, 2026
Extension: Oct 15, 2026
Form: Form 568
LLC returns follow the partnership calendar-year due date.
Nonprofit deadline
Due: May 15, 2026
Extension: Dec 15, 2026
Form: Form 199 / 199N
CA allows a 7-month extension for exempt organizations.
Estimated Tax Payments
View all quarterly estimated payment due dates for California.
FAQ
Does California conform to federal due dates?
Many California deadlines follow the federal calendar. Always confirm on California Franchise Tax Board.
Where can I file California tax forms?
Visit California Franchise Tax Board at https://www.ftb.ca.gov for official forms and e-file options.