Here’s the full IRS and Delaware tax calendar for calendar-year C-Corps (Jan 1–Dec 31):
Even if you’re:
Pre-revenue
Funded by SAFE or equity rounds
A solo founder
You still face filing and compliance deadlines. Missing just one can lead to:
IRS late penalties
Loss of Delaware good standing
Delays in fundraising or exits
TaxHero AI helps you:
Track your startup’s exact tax deadlines
File the right forms (Form 1120, Franchise Tax, etc.)
Avoid penalties or compliance gaps
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Form 1120 Guide: Your C-Corp tax return (due April 15)
Form 5472 for Foreign Founders: Mandatory for foreign-owned startups
Franchise Tax Guide: Due March 1, even for $0 revenue
Startup Tax Deductions: Lower your tax bill legally
Form 7004 Extension Filing: Use this if you're running late
You may still owe 2024 tax filings (even with $0 activity). Talk to a startup tax advisor or use TaxHero AI to auto-detect your obligations.
Your Form 1120 deadline is the 15th day of the 4th month after your fiscal year-end. This calendar assumes a standard Jan 1 – Dec 31 fiscal year.
It should be tracked internally. It’s due 30 days from your equity grant, not on a fixed date. Learn more here → 83(b) Election Guide
This calendar is your startup's IRS and Delaware compliance roadmap. Stay ahead. File early. Avoid surprises.
Start by finding out what your company needs to do.
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