Tax
Form 1120-S (S-corp Return)
Quick definition
Annual return for S-corporations reporting income that passes through to owners on Schedule K-1.
Form 1120-S reports the S-corp's income, deductions, gains, losses, and credits — but the S-corp itself usually doesn't pay tax. Instead, each shareholder receives a K-1 with their pro-rata share of income/losses and reports it on their personal 1040. Due March 15 (or 15th day of 3rd month after fiscal year end). 6-month extension available via Form 7004.
Related tax terms
R&D Tax Credit
Federal credit for qualified research expenses, usable against payroll tax by startups.
Delaware Franchise Tax
Annual tax for Delaware corporations, often quoted wildly too high if calculated incorrectly.
Nexus (Sales Tax)
The connection with a state that triggers a tax-collection obligation.
QSBS (Qualified Small Business Stock)
Tax exemption for gains on qualifying startup stock held 5+ years.
Frequently asked questions
- What is Form 1120-S (S-corp Return)?
- Form 1120-S reports the S-corp's income, deductions, gains, losses, and credits — but the S-corp itself usually doesn't pay tax. Instead, each shareholder receives a K-1 with their pro-rata share of income/losses and reports it on their personal 1040. Due March 15 (or 15th day of 3rd month after fiscal year end). 6-month extension available via Form 7004.
- Why is Form 1120-S (S-corp Return) important for startups?
- Form 1120-S (S-corp Return) is a tax concept that matters for startup founders because it directly affects fundraising readiness, financial decision-making, or operational discipline at the stage where mistakes are expensive to undo. Founders who understand it have a meaningfully easier time in diligence, board meetings, and investor conversations.
- What category does Form 1120-S (S-corp Return) belong to?
- Form 1120-S (S-corp Return) is a Tax term in the StartupCFO finance glossary — alongside other tax concepts that founders, CFOs, and accountants use in daily startup operations and reporting.
- Where can I learn more about Form 1120-S (S-corp Return)?
- Beyond this definition, see the related tax terms below, or explore StartupCFO's insights and tools that put Form 1120-S (S-corp Return) in context. For specific situations, talk to a fractional CFO who can walk through your numbers.
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