Tax & Business Resources
Calculators, guides, and quick reference for S-Corps, partnerships, C-Corps, and growing companies. From CPAs who specialize in pass-through entities.
Tax Calculators & Tools
S-Corp Tax Calculator
Estimate tax savings if you elect S-Corp status
Use CalculatorQBI Deduction Calculator
Calculate your Section 199A qualified business income deduction
Use CalculatorSelf-Employment Tax Calculator
Calculate Schedule C self-employment tax liability
Use CalculatorSection 179 Vehicle List
See which vehicles qualify for the Section 179 deduction
View List2026 Quick Reference
Key Deadlines
Rates & Limits
Tax Guides by Entity Type
Popular Articles
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Popular Articles
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401(k), Roth conversions, and retirement tax strategies
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Frequently Asked Questions
What tax form does an S-Corp file?
S-Corporations file Form 1120-S annually. This is an information return that reports the company’s income, deductions, and credits. The S-Corp itself doesn’t pay income tax – instead, income passes through to shareholders via Schedule K-1, which shareholders report on their personal returns.
When are partnership tax returns due?
Partnership returns (Form 1065) are due March 15th for calendar-year partnerships. For 2026, the deadline is March 16, 2026 (the 15th falls on a Sunday). Extensions extend the deadline to September 15, 2026. Partnerships must provide K-1s to partners by the filing deadline.
How do I calculate self-employment tax?
Self-employment tax is 15.3% of net self-employment income (12.4% Social Security + 2.9% Medicare). You pay SE tax on 92.35% of net earnings. For 2026, the Social Security portion applies to the first $184,500 of combined wages and self-employment income. Use our self-employment tax calculator for a quick estimate.
What is the Section 179 deduction limit for 2026?
The Section 179 deduction limit for 2026 is $2,560,000. This allows businesses to deduct the full purchase price of qualifying equipment and software in the year of purchase, rather than depreciating over time. The phase-out threshold begins at $4,090,000 in total equipment purchases.
What is the QBI deduction income threshold?
For 2026, the QBI (Section 199A) deduction phase-out begins at $197,300 for single filers and $394,600 for married filing jointly. Below these thresholds, most pass-through business owners can deduct up to 20% of qualified business income. Above these thresholds, specified service businesses face limitations.
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