Important Tax Deadlines for 2026

It’s a good time to review your 2026 tax and compliance deadlines. Saying organized now helps prevent missed filings, penalties, and last-minute stress. Below is a summary of key federal, California, and local deadlines through January 2026.

• January 15, 2026: Fourth quarter estimated tax payments for 2025 are due.
• February 2, 2026: Quarterly California sales tax returns for Q4 2025 and electronic 1099 filings are due.
• March 2, 2026: Los Angeles Business Tax Renewal deadline.
• March 16, 2026: Partnerships and S Corporations file 2025 returns or request an extension.
• April 15, 2026: Individual and C Corporation tax returns and first-quarter estimated tax payments for 2026 are due.
• April 30, 2026: Q1 2026 California sales tax returns are due.
• June 15, 2026: Second quarter estimated tax payments for 2026.
• July 31, 2026: Q2 2026 California sales tax returns are due.
• September 15, 2026: Extended deadline for Partnerships and S Corporations and third-quarter estimated tax payments.
• October 15, 2026: Extended deadline for individual and C Corporation tax returns.
• November 2, 2026: Q3 2026 California sales tax returns are due.
• February 1, 2027: Q4 2026 California sales tax returns are due.

Planning ahead and using professional accounting services can help you meet these deadlines with ease. Contact us to stay on track in 2026.