Business Tax Guides
Long-form, evidence-based guides on US small business taxes. LLC vs S-Corp vs C-Corp decision math, the 20% Section 199A QBI deduction most owners miss, IRS-compliant reasonable salary for S-Corp owners, business deductions the IRS actually audits, and quarterly estimated tax safe harbor rules.
LLC vs S-Corp vs C-Corp: The Real Tax Math for Small Businesses
A step-by-step tax comparison of the three main US business entity types, the self-employment tax savings of S-Corp election, and the income level where each structure wins.
Section 199A QBI Deduction: The 20% Savings Most LLC Owners Miss
How the Qualified Business Income deduction works, who qualifies, the income thresholds, the specified service trade phase-out, and how to structure your business to maximize the 20% deduction.
S-Corp Reasonable Salary: The IRS Rule That Triggers Audits
How the IRS determines "reasonable compensation" for S-Corp owners, the audit triggers, the factors that matter, and how to document and defend your salary choice.
Business Tax Deductions: What the IRS Actually Audits
The biggest legitimate small business deductions, the IRS audit triggers to avoid, documentation requirements that survive audit, and the deductions that look legitimate but get rejected.
Quarterly Estimated Taxes: The Safe Harbor Rule That Avoids Penalties
How quarterly estimated taxes work for self-employed and business owners, the safe harbor rules that avoid underpayment penalties, calculation methods, and the IRS penalty structure.