Check our 2026 Tax Deadlines For C-Corp Startups or Click for your customized tax compliance calendar by startup hub
Startup companies based in Miami have several important tax deadlines in 2026, including the April 15th federal and Florida tax return filings (which can be extended until October 15th). Additionally, Florida and the federal government have various tax filings due on the dates listed below.
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.
Miami 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 Miami startup will pay a minimum of $400, which increases if you have significant funding.
For Miami 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).
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 Miami 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 Miami startup employees to make contributions to Individual Retirement Accounts (IRAs) for 2025 (Employee Benefits).
Miami startups can claim Research & Development Tax Credits on Form 941.
Florida Estimated Corporate Income Tax payment due – Installment #1.
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 Miami startups if extension was filed.
Extended due date for Florida Corporate Income Tax Return.
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 Miami Startup Tax Deadlines
Florida Estimated Corporate Income Tax payment due – Installment #4 (For Prior Year)
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.
Miami 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 Miami startup will pay a minimum of $400, which increases if you have significant funding.
For Miami 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).
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 Miami 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 Miami startup employees to make contributions to Individual Retirement Accounts (IRAs) for 2025 (Employee Benefits).
Miami startups can claim Research & Development Tax Credits on Form 941.
Florida Corporate Income Tax Return due date (can be extended to November 1).
Florida Estimated Corporate Income Tax payment due – Installment #1.
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).
Florida Estimated Corporate Income Tax payment due – Installment #2.
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).
Florida Estimated Corporate Income Tax payment due – Installment #3.
C Corp Form 1120 Tax Return final due date for Miami startups if extension was filed.
Extended due date for Florida Corporate Income Tax Return.
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).
Florida Estimated Corporate Income Tax payment due – Installment #4.
Federal Quarterly Estimated Tax 4th installment (fourth quarter 2026).
Note: The federal tax deadline in 2026 falls on April 15. The federal extension deadline for 2026 is October 15. Most states usually follow the same calendar for state income tax returns.
If your Delaware C-Corp Miami funded startup needs tax help contact us today!
MIAMI, STARTUPS AND TAXES
Miami has solidified its status as the fastest-growing U.S. city for technology startups in 2026, now ranked 11th nationally and climbing into the top 30 global tech hubs. The city’s startup environment is valued near $95 billion, with venture capital investments projected to exceed $4.6 billion in 2025 – 35% growth year-over-year – across more than 340 deals. Miami is home to over 2,000 startups, with strengths in fintech, climate tech, healthtech, AI, and quantum computing. Major tech employers such as Microsoft, Apple, and Spotify have opened local offices, while homegrown unicorns like Pipe and Magic Leap contribute to a robust pipeline of innovation and exits.
The local talent pool is highly educated and offers a distinct advantage with bilingual professionals, supporting global expansion and regional access to Latin American markets. A wide array of support organizations – Mana Tech, The Lab Miami, Endeavor Miami, and the Miami Downtown Development Authority – provides founders with mentorship, networks, and financial incentives, while high-profile events such as eMerge Americas and the Florida Venture Capital Conference further connect startups with investors and resources.
Key taxing authorities for Miami-based companies in 2026 include:
With rapid growth, strategic ecosystem assets, and continued investor interest, Miami presents a prime launchpad for innovative founders looking to scale ventures in 2026.
For Miami-based businesses, the critical tax deadlines in 2026 include the April 15th state and federal tax return deadlines (which can be extended until October 15th) and the various federal and state filings listed in the calendar above.
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 Miami Startup Tax Deadlines
Florida Estimated Corporate Income Tax payment due – Installment #4 (For Prior Year)
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 Miami 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.
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 Miami 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 Miami startup employees to make contributions to Individual Retirement Accounts (IRAs) for 2023 (Employee Benefits).
Miami startups can claim Research & Development Tax Credits on Form 941.
Florida Corporate Income Tax Return due date (can be extended to November 1).
Florida Estimated Corporate Income Tax payment due – Installment #1.
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).
Florida Estimated Corporate Income Tax payment due – Installment #2.
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).
Florida Estimated Corporate Income Tax payment due – Installment #3.
C Corp Form 1120 Tax Return final due date for Miami startups if extension was filed.
Claim your Research & Development Tax Credits on Form 941.
Extended due date for Florida Corporate Income Tax Return.
Delaware Quarterly Estimated Franchise Tax, Pay 20% of estimated annual amount (if annual amount expected to exceed $5,000).
Florida Estimated Corporate Income Tax payment due – Installment #4.
Federal Quarterly Estimated Tax 4th installment (fourth quarter 2024).
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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