Check our 2026 Tax Deadlines For C-Corp Startups or Click for your customized tax compliance calendar by startup hub
In 2026, San Jose has many corporate tax deadlines beyond the traditional April 15th tax return date. San Jose’s business tax is due on the 15th day of the calendar month in which the business began. See the calendar below for a more complete list.
Claim Research & Development Tax Credits on Form 941, and file annual Federal Unemployment Tax Act (FUTA) return on Form 940. Use our handy calculator to estimate your possible research and development tax credit.
San Jose startups should send 1099s to contractors. Send W2s to employees and e-file 1099-MISC for non-employee compensation with the IRS. Or file Form 8809 for a 30-day extension to file W2s and 1099-MISC for non-employee compensation.
Delaware Annual Franchise Report filing deadline. Your San Jose startup will pay a minimum of $400, which increases if you have significant funding.
For San Jose startups, IRS ACA Compliance 1094-B, 1095-B, 1094-C, and 1095-C filings are due (if paper-filing, due April 1 if eFiling). File Form 8809 for a 30-day extension.
Send 1095-B and 1095-C forms to employees.
IRS 30-day automatic extension: provide Form 1095-B and Form 1095C to employees.
IRS ACA Compliance 1094-B, 1095-B, 1094-C, and 1095-C filings are due (e-file).
Deadline to file California Corporation Franchise or Income Tax Return (Form 100). Minimum amount due is $800.
C Corp Form 1120 Tax Return due. The Federal Form 1120 is the U.S. Corporation Income Tax Return, which the IRS has companies use to report their income, losses, credits, etc., and to figure the income tax liability of the corporation. Can extend the deadline to Oct. 15. All San Jose startups are required to file this Federal form by this deadline unless they file an extension.
Federal Quarterly Estimated Tax 1st installment (first quarter 2026).
File the R&D Tax Credit Form 6765 with your tax return. Can extend to October 15. We strongly recommend working with a qualified CPA to prepare this form in conjunction with your Form 1120 if your company is going to be acquired by a major technology company, that company’s CFO will use a strong tax team to do due diligence on this.
Due date for San Jose startup employees to make contributions to Individual Retirement Accounts (IRAs) for 2025 (Employee Benefits).
San Jose startups can claim Research & Development Tax Credits on Form 941.
Delaware Quarterly Estimated Franchise Tax. Pay 40% of estimated annual amount (if annual amount expected to exceed $5,000).
Federal Quarterly Estimated Tax 2nd installment (second quarter 2026).
Claim Research & Development Tax Credits on Form 941.
Delaware Quarterly Estimated Franchise Tax. Pay 20% of your estimated annual amount (if annual amount expected to exceed $5,000).
Federal Quarterly Estimated Tax 3rd installment (third quarter 2026).
C Corp Form 1120 Tax Return final due date for San Jose startups if extension was filed.
Claim your Research & Development Tax Credits on Form 941.
Delaware Quarterly Estimated Franchise Tax, Pay 20% of estimated annual amount (if annual amount expected to exceed $5,000).
Federal Quarterly Estimated Tax 4th installment (fourth quarter 2026).
Click The Links To Learn More About These Filings And 2026 San Jose Startup Tax Deadlines
Federal Quarterly Estimated Tax 4th installment (fourth quarter 2025).
Claim Research & Development Tax Credits on Form 941, and file annual Federal Unemployment Tax Act (FUTA) return on Form 940. Use our handy calculator to estimate your possible research and development tax credit.
San Jose startups should send 1099s to contractors. Send W2s to employees and e-file 1099-MISC for non-employee compensation with the IRS. Or file Form 8809 for a 30-day extension to file W2s and 1099-MISC for non-employee compensation.
Delaware Annual Franchise Report filing deadline. Your San Jose startup will pay a minimum of $400, which increases if you have significant funding.
For San Jose startups, IRS ACA Compliance 1094-B, 1095-B, 1094-C, and 1095-C filings are due (if paper-filing, due April 1 if eFiling). File Form 8809 for a 30-day extension.
Send 1095-B and 1095-C forms to employees.
IRS 30-day automatic extension: provide Form 1095-B and Form 1095C to employees.
IRS ACA Compliance 1094-B, 1095-B, 1094-C, and 1095-C filings are due (e-file).
571-L Business Property Tax for County of Santa Clara filing due. Initial deadline.
Deadline to file California Corporation Franchise or Income Tax Return (Form 100). Minimum amount due is $800.
C Corp Form 1120 Tax Return due. The Federal Form 1120 is the U.S. Corporation Income Tax Return, which the IRS has companies use to report their income, losses, credits, etc., and to figure the income tax liability of the corporation. Can extend the deadline to Oct. 15. All San Jose startups are required to file this Federal form by this deadline unless they file an extension.
Federal Quarterly Estimated Tax 1st installment (first quarter 2026).
File the R&D Tax Credit Form 6765 with your tax return. Can extend to October 15. We strongly recommend working with a qualified CPA to prepare this form in conjunction with your Form 1120 if your company is going to be acquired by a major technology company, that company’s CFO will use a strong tax team to do due diligence on this.
Due date for San Jose startup employees to make contributions to Individual Retirement Accounts (IRAs) for 2025 (Employee Benefits).
San Jose startups can claim Research & Development Tax Credits on Form 941.
571-L Business Property Tax filing due. Final date to avoid 10% penalty.
Delaware Quarterly Estimated Franchise Tax. Pay 40% of estimated annual amount (if annual amount expected to exceed $5,000).
Federal Quarterly Estimated Tax 2nd installment (second quarter 2026).
Claim Research & Development Tax Credits on Form 941.
Delaware Quarterly Estimated Franchise Tax. Pay 20% of your estimated annual amount (if annual amount expected to exceed $5,000).
Federal Quarterly Estimated Tax 3rd installment (third quarter 2026).
C Corp Form 1120 Tax Return final due date for San Jose startups if extension was filed.
Claim your Research & Development Tax Credits on Form 941.
Delaware Quarterly Estimated Franchise Tax, Pay 20% of estimated annual amount (if annual amount expected to exceed $5,000).
Federal Quarterly Estimated Tax 4th installment (fourth quarter 2026).
California Statement of Information due. Pay $25. Most corporations file annually by the last day of their registration anniversary month.
Note: The federal tax deadline for 2026 is April 15 and the federal extension deadline is October 15.
How Much Does a Startup Tax Return Cost? Try Kruze Consulting’s Tax Preparation Pricing Tool.
If your Delaware C-Corp San Jose funded startup needs tax help contact us today!
SAN JOSE, STARTUPS AND TAXES
San Jose continues to establish itself as a top-tier innovation and AI hub in 2026, boasting a vibrant ecosystem of 91 venture-backed AI companies valued at more than $6 billion and over 23 downtown AI startups collectively worth $1.3 billion. The city’s pro-innovation environment is strengthened by dedicated programs like the AI Incentive Program, which awards grants and professional support to early-stage AI companies tackling pressing issues in healthcare, sustainability, and deep tech. San Jose’s new IT Innovation Hub further streamlines public-private collaboration by enabling startups to directly pitch solutions to city decision-makers – creating fresh opportunities for integrating cutting-edge technologies into essential services.
The presence of major tech employers including Adobe, Cisco, PayPal, and eBay continues to seed the local talent pool, while Santa Clara University and San Jose State University power the next generation of founders. Programs like the AI Upskilling Program and business-friendly initiatives such as tax waivers for downtown office leasing reinforce San Jose’s appeal for both established ventures and emerging startups.
Key taxing authorities for San Jose-based companies in 2026 are:
San Jose’s highly collaborative and supportive innovation ecosystem makes it a hotspot for founders building in AI, software, and core tech sectors in 2026.
In 2026, San Jose has many corporate tax deadlines beyond the traditional April 15th tax return date. San Jose’s business tax is due on the 15th day of the calendar month in which the business began. See the calendar above for a more complete list.
2025 startup tax deadlines are supplied for reference purposes only, and should not be used when making decisions in 2026 or beyond. Always consult your tax professional, and see our disclaimer below.
Click The Links To Learn More About These Filings And 2025 San Jose Startup Tax Deadlines
Claim Research & Development Tax Credits on Form 941, and file annual Federal Unemployment Tax Act (FUTA) return on Form 940. Use our handy calculator to estimate your possible research and development tax credit.
Delaware Annual Franchise Report filing deadline. Your San Jose startup will pay a minimum of $400, which increases if you have significant funding.
IRS 30-day automatic extension: provide Form 1095-B and Form 1095C to employees.
571-L Business Property Tax for County of Santa Clara filing due. Initial deadline.
Deadline to file California Corporation Franchise or Income Tax Return (Form 100). Minimum amount due is $800.
C Corp Form 1120 Tax Return due. The Federal Form 1120 is the U.S. Corporation Income Tax Return, which the IRS has companies use to report their income, losses, credits, etc., and to figure the income tax liability of the corporation. Can extend the deadline to Oct. 15. All San Jose startups are required to file this Federal form by this deadline unless they file an extension.
Federal Quarterly Estimated Tax 1st installment (first quarter 2024).
File the R&D Tax Credit Form 6765 with your tax return. Can extend to October 15. We strongly recommend working with a qualified CPA to prepare this form in conjunction with your Form 1120 if you are a high-growth startup – if your company is going to be acquired by a major technology company, that company’s CFO will use a strong tax team to do due diligence on this.
Due date for San Jose startup employees to make contributions to Individual Retirement Accounts (IRAs) for 2023 (Employee Benefits).
San Jose startups can claim Research & Development Tax Credits on Form 941.
571-L Business Property Tax filing due. Final date to avoid 10% penalty.
Delaware Quarterly Estimated Franchise Tax. Pay 40% of estimated annual amount (if annual amount expected to exceed $5,000).
Federal Quarterly Estimated Tax 2nd installment (second quarter 2024).
Claim Research & Development Tax Credits on Form 941 .
Delaware Quarterly Estimated Franchise Tax. Pay 20% of your estimated annual amount (if annual amount expected to exceed $5,000).
Federal Quarterly Estimated Tax 3rd installment (third quarter 2024).
C Corp Form 1120 Tax Return final due date for San Jose startups if extension was filed.
Claim your Research & Development Tax Credits on Form 941.
Delaware Quarterly Estimated Franchise Tax, Pay 20% of estimated annual amount (if annual amount expected to exceed $5,000).
Federal Quarterly Estimated Tax 4th installment (fourth quarter 2024).
California Statement of Information due. Pay $25.
View tax compliance dates for Austin, Boston, New York City, Palo Alto, San Francisco, Santa Monica, Seattle, Washington DC, Atlanta, Salt Lake City, Mountain View, Chicago, Dallas, Miami, and San Jose
How Much Does a Startup Tax Return Cost? Try Kruze Consulting's Tax Preparation Pricing Tool.
How much can your startup save in payroll taxes? Estimate your R&D tax credit using our free calculator.
Every startup is different and so are its tax compliance needs. This is only a guideline. Please consult your tax professional. IRS Circular 230 Disclaimer: To ensure compliance with IRS Circular 230, any U.S. federal tax advice provided in this communication is not intended or written to be used, and it cannot be used by the recipient or any other taxpayer for the purpose of avoiding tax penalties that may be imposed on the recipient or any other taxpayer. Copyright © Kruze Consulting
Check our 2026 Tax Deadlines For C-Corp Startups or Click for your customized tax compliance calendar by startup hub
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