C-Corp vs. S-Corp: Tax Rates, Double Taxation, QSBS, and Which Structure Wins

By Yarik Yarosh, CPA ·September 5, 2026 ·6 min read

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

The C-Corp and S-Corp are both corporations under state law, but they are taxed completely differently. A C-Corp is a separate taxpayer: it pays a flat 21% federal corporate income tax on its profits (Form 1120), and when those profits are distributed to shareholders as dividends, the shareholders pay tax again at qualified dividend rates (0%, 15%, or 20% plus the 3.8% NIIT). This “double taxation” is the C-Corp’s primary disadvantage. An S-Corp is a pass-through entity: the corporation itself pays no federal income tax (Form 1120-S), and all income passes through to shareholders on Schedule K-1, taxed at their individual rates (10-37%). The S-Corp avoids double taxation entirely. However, the C-Corp has advantages in specific situations: the 21% corporate rate is lower than most individual rates for retained earnings, the QSBS exclusion (IRC 1202) can eliminate capital gains tax on a sale, and C-Corps can deduct the full cost of employee fringe benefits (including for owner-employees above 2% shareholders).

✓Key takeaway

C-Corp vs. S-Corp tax comparison:

Factor	C-Corp	S-Corp
Entity-level tax	21% flat rate	None (pass-through)
Shareholder tax on distributions	Qualified dividend rates (0/15/20%)	No additional tax (already taxed on K-1)
Total tax on distributed profits	21% + 15-20% = approximately 36-40%	Individual rates (10-37%) + SE tax on salary
Retained earnings tax rate	21% (no shareholder tax until distributed)	Individual rates (10-37%, taxed even if not distributed)
QBI deduction (Section 199A)	NOT eligible	Eligible (20% deduction for qualifying income)
FICA on owner compensation	15.3% on wages (same as S-Corp)	15.3% on salary only (distributions exempt)
Fringe benefits for owner-employee	Fully deductible (health insurance, group term life, etc.)	Not deductible for 2%+ shareholders (included in W-2)
QSBS exclusion (IRC 1202)	Eligible (up to $10M tax-free gain on sale)	NOT eligible
Accumulated earnings penalty	20% surtax on unreasonable accumulations	No penalty (pass-through)
Number of shareholders	Unlimited	Maximum 100
Shareholder types	Any (individuals, corps, trusts, foreigners)	Restricted (US individuals, certain trusts, no corps)
Classes of stock	Multiple (common, preferred, etc.)	One class only

When the C-Corp wins:

Scenario	Why C-Corp Is Better
Planning to sell for $1M+ and holding 5+ years	QSBS: $0 federal tax on up to $10M gain
Retaining earnings for growth (not distributing)	21% corporate rate < 32-37% individual rate
Significant fringe benefits for owner	Health insurance, group term life fully deductible
Venture capital / investor funding	Multiple stock classes, unlimited shareholders
Foreign shareholders	S-Corp cannot have non-resident alien shareholders

When the S-Corp wins:

Scenario	Why S-Corp Is Better
Distributing most profits to owners annually	Avoids double taxation
FICA savings needed (salary/distribution split)	Distributions not subject to FICA
QBI deduction available (non-SSTB under threshold)	20% deduction reduces effective rate
Simple ownership (1-2 US shareholders)	Pass-through simplicity
Lifestyle business (not planning to sell)	No double tax, no entity-level tax

How do the numbers compare at different income levels?

Hypothetical example

Round numbers. A single owner. Comparing C-Corp vs. S-Corp at $150,000 net profit. All profits distributed.

S-Corp ($150,000 net profit, all distributed):

Item	Amount
Owner salary	$70,000
FICA on salary (15.3%)	$10,710
S-Corp distribution	$80,000
FICA on distribution	$0
Taxable income (K-1: $150,000 total)	$150,000
QBI deduction (20% of $150,000)	($30,000)
Taxable after QBI and standard deduction	$105,000
Federal income tax	approximately $16,600
Total FICA	$10,710
Total federal tax	$27,310
Effective rate	18.2%

C-Corp ($150,000 net profit, all distributed as salary + dividend):

Option A: All as salary (no double tax, but high FICA):

Item	Amount
Owner salary	$150,000
FICA on salary (15.3% up to $176,100)	$22,950
Corporate taxable income	$0 (salary is deductible)
Corporate tax	$0
Individual taxable income	$150,000
Federal income tax (no QBI deduction for C-Corp)	approximately $24,600
Total federal tax	$47,550
Effective rate	31.7%

This is clearly worse because FICA applies to the full $150,000 (no salary/distribution split).

Option B: $70,000 salary + $80,000 dividend (after corporate tax):

Item	Amount
Corporate revenue	$150,000
Owner salary (deductible)	($70,000)
FICA on salary	$10,710
Corporate taxable income	$80,000
Corporate tax (21%)	$16,800
After-tax corporate earnings	$63,200
Dividend to owner	$63,200
Qualified dividend tax (15%)	$9,480
Individual income tax on $70,000 salary	approximately $8,200
Total federal tax	$45,190
Effective rate on $150,000	30.1%

Comparison at $150,000 (all distributed):

Structure	Total Tax	Effective Rate
S-Corp	$27,310	18.2%
C-Corp (salary only)	$47,550	31.7%
C-Corp (salary + dividend)	$45,190	30.1%

The S-Corp saves $17,880 per year at $150,000 when all profits are distributed. The C-Corp’s double taxation is a clear disadvantage for distribution-heavy businesses.

But what if the C-Corp RETAINS the earnings?

Item	C-Corp (retained)	S-Corp (must report)
Corporate taxable income	$80,000	N/A (pass-through)
Corporate tax	$16,800 (21%)	N/A
Owner’s current-year tax on retained earnings	$0 (not distributed)	$80,000 x marginal rate (24-32%) = $19,200-$25,600
Cash available for reinvestment	$63,200	$80,000 - $19,200 = $60,800

When retaining earnings for growth, the C-Corp keeps MORE cash for reinvestment ($63,200 vs. $60,800) because the 21% corporate rate is lower than the owner’s 24-32% individual rate. Over 10 years of compounding, this difference is significant.

The QSBS play (5+ year exit): If the C-Corp grows from $150,000 in Year 1 to a $3,000,000 sale in Year 7:

Structure	Tax on Sale
C-Corp with QSBS	$0 (100% exclusion, stock held 7 years)
S-Corp	$3,000,000 x 20% LTCG = $600,000

The QSBS exclusion makes the C-Corp dramatically better for a sale event, overcoming years of double taxation on distributions.

The break-even question: How many years of C-Corp double taxation does the QSBS exclusion offset?

Annual double-tax cost: $17,880 (vs. S-Corp) QSBS tax savings on sale: $600,000 Break-even: $600,000 / $17,880 = 33.6 years

If the business is sold within 33 years, the QSBS exclusion more than compensates for the annual double taxation. For a business planning a 5-10 year exit, the C-Corp with QSBS is clearly better.

For a lifestyle business with no exit plan: the S-Corp is better (no double tax, QBI deduction, FICA savings).

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

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Cite this page

Yarik Yarosh, CPA. "C-Corp vs. S-Corp: Tax Rates, Double Taxation, QSBS, and Which Structure Wins." Blue Cloud CPA, September 5, 2026. https://bluecloudcpa.com/guides/small-business-c-corp-vs-scorp-tax-comparison

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