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Tax

Estimated Tax Payments

Quick definition

Quarterly tax payments required for corporations expecting to owe $500+ in tax for the year. Due Apr 15, Jun 15, Sep 15, Dec 15.

C-corps that expect to owe $500+ in federal income tax must pay quarterly estimates: 25% of prior year's tax liability (or current year if larger), due on the 15th day of the 4th, 6th, 9th, and 12th month of the tax year. Underpayment penalties apply. Safe harbor for individuals: pay 100% of prior-year tax (110% if prior-year AGI exceeded $150,000; $75,000 if married filing separately). Large corporations (taxable income of $1M+ in any of the three prior years) cannot use the prior-year safe harbor except for Q1. S-corp passthrough income is paid via owner's individual quarterly estimates on Form 1040-ES.

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Frequently asked questions

What is Estimated Tax Payments?
C-corps that expect to owe $500+ in federal income tax must pay quarterly estimates: 25% of prior year's tax liability (or current year if larger), due on the 15th day of the 4th, 6th, 9th, and 12th month of the tax year. Underpayment penalties apply. Safe harbor for individuals: pay 100% of prior-year tax (110% if prior-year AGI exceeded $150,000; $75,000 if married filing separately). Large corporations (taxable income of $1M+ in any of the three prior years) cannot use the prior-year safe harbor except for Q1. S-corp passthrough income is paid via owner's individual quarterly estimates on Form 1040-ES.
Why is Estimated Tax Payments important for startups?
Estimated Tax Payments is a tax concept that matters for startup founders because it shows up in fundraising readiness, financial decision-making, and operational discipline at the stage where mistakes are expensive to undo. Founders who understand it are better prepared for diligence, board meetings, and investor conversations.
What category does Estimated Tax Payments belong to?
Estimated Tax Payments is a Tax term in the StartupCFO finance glossary, alongside other tax concepts that founders, CFOs, and accountants use in startup operations and reporting.
Where can I learn more about Estimated Tax Payments?
Beyond this definition, see the related tax terms below, or explore StartupCFO's insights and tools that put Estimated Tax Payments in context. For specific situations, talk to a fractional CFO who can walk through your numbers.

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