Payroll Tax vs Income Tax: What Small Business Owners Actually Pay (And Why SE Tax Hurts)

By Yarik Yarosh, CPA ·September 5, 2026 ·3 min read

Written by Yarik Yarosh, CPA (US & Canada) September 5, 2026 · FL CPA license AC61704 · CPA Ontario

Most small business owners focus on their income tax bracket and overlook the larger burden: self-employment tax. For a sole proprietor earning $100,000 in net business income, self-employment tax is $14,130, more than the federal income tax in many cases. Understanding the components of what you actually pay, and how the S-Corp election changes the math, is the foundation of effective tax planning.

✓Key takeaway

The two tax systems for business owners:

Income tax (graduated rates, 2025):

10%: $0-$11,925 (single)
12%: $11,926-$48,475
22%: $48,476-$103,350
24%: $103,351-$197,300
32%: $197,301-$250,525
35%: $250,526-$626,350
37%: over $626,350

Income tax applies to ALL taxable income: wages, business income, investment income, retirement distributions, etc. Standard deduction ($15,000 single, $30,000 MFJ in 2025) reduces taxable income.

Self-employment tax / FICA (flat rates, applied to business income):

Social Security: 12.4% on the first $176,100 (2025) of combined wages and SE income
- Employees pay 6.2%, employer pays 6.2%
- Self-employed pay the full 12.4%
Medicare: 2.9% on ALL earned income (no cap)
- Employees pay 1.45%, employer pays 1.45%
- Self-employed pay the full 2.9%
Additional Medicare Tax: 0.9% on earned income above $200,000 (single) / $250,000 (MFJ)
- Employee only; self-employed pay it on SE income

Combined SE tax rate: 15.3% (12.4% + 2.9%) on the first $176,100, then 2.9% (Medicare only) above that, plus 0.9% above $200,000.

Why SE tax “hurts”:

It’s a FLAT tax with no brackets, deductions, or credits (except the 50% above-the-line deduction for the employer-equivalent portion)
It applies from dollar one of net business income
A sole proprietor earning $50,000 pays approximately $7,065 in SE tax BEFORE paying any income tax
Combined with income tax, the effective rate on the first $50,000 of business income is approximately 28-30% (SE tax + 12% income bracket)

How does the S-Corp change the math?

Hypothetical example

Round numbers. A business owner earns $150,000 in net business income (after business expenses). Single filer, no other income.

As sole proprietor (Schedule C):

SE tax: $150,000 x 92.35% x 15.3% = $21,194
50% SE tax deduction: $10,597
Taxable income: $150,000 - $10,597 - $15,750 (standard deduction) = $124,403
Income tax: approximately $21,000
QBI deduction: $150,000 x 20% = $30,000 (reduces taxable income by $30,000)
Revised income tax (with QBI): approximately $14,400
Total federal tax: $21,194 + $14,400 = $35,594
Effective rate: 23.7%

As S-Corp (reasonable salary $65,000, distributions $85,000):

FICA on salary:
- Employee share: $65,000 x 7.65% = $4,973
- Employer share: $65,000 x 7.65% = $4,973
- Total FICA: $9,945
No SE tax on $85,000 distribution
Taxable income: $65,000 salary + $85,000 K-1 income - $15,000 standard deduction = $135,000
- Wait: employer FICA ($4,973) is deductible by the S-Corp, reducing K-1 income
- Revised K-1: $85,000 - $4,973 = $80,027
- Taxable income: $65,000 + $80,027 - $15,000 = $130,027
QBI deduction: $80,027 x 20% = $16,005 (QBI is K-1 income, not salary)
Revised taxable income: $130,027 - $16,005 = $114,022
Income tax: approximately $18,500
Total federal tax: $9,945 + $18,500 = $28,445
Effective rate: 19.0%

Annual savings with S-Corp: $7,149

The savings come from avoiding SE tax on the $85,000 distribution ($85,000 x 15.3% = $13,005), partially offset by the reduced QBI deduction (QBI is calculated on K-1 income only, not salary, so the deduction is smaller). The S-Corp also has additional costs (payroll processing, S-Corp tax return preparation) of approximately $1,500-$3,000, netting $4,149-$5,649 in true savings.

Illustrative numbers only, not a real client and not advice for your facts.

Related guides:

Trust Fund Recovery Penalty (TFRP): Personal Liability for Unpaid Payroll Taxes (IRC 6672)

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Cite this page

Yarik Yarosh, CPA. "Payroll Tax vs Income Tax: What Small Business Owners Actually Pay (And Why SE Tax Hurts)." Blue Cloud CPA, September 5, 2026. https://bluecloudcpa.com/guides/small-business-payroll-tax-vs-income-tax

This guide is general information, not tax advice for your specific situation. Which points apply, and how, depends on your facts.