C-Corp vs. S-Corp: Complete Entity Selection Guide for Business Owners

By Yarik Yarosh, CPA ·September 5, 2026 ·Updated September 23, 2026 ·8 min read

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

The C-Corp vs. S-Corp decision is not a one-size-fits-all analysis, and the conventional wisdom (“always choose an S-Corp for a small business”) has become less accurate since the Tax Cuts and Jobs Act lowered the C-Corp rate to 21% and created the IRC 199A QBI deduction for pass-through entities. The right answer depends on five variables: (1) how much of the business income is distributed to the owner vs. reinvested, (2) whether the business is an SSTB (which eliminates the QBI deduction at higher income levels), (3) the owner’s personal marginal tax rate, (4) whether the business plans to seek outside investment or pursue QSBS, and (5) the owner’s exit strategy. Under IRC 1361, an S-Corp election imposes several structural restrictions: only one class of stock, 100 or fewer shareholders, all shareholders must be U.S. citizens or residents (or certain trusts and estates), and no corporate or partnership shareholders. These restrictions prevent S-Corps from issuing preferred stock, taking on international investors, or using the complex capital structures that venture-backed companies require. C-Corps have no such restrictions.

✓Key takeaway

C-Corp vs. S-Corp comparison:

Factor	C-Corp	S-Corp
Entity-level tax	21% flat	None (pass-through)
Owner tax on distributions	23.8% (qualified dividends)	$0 (already taxed on K-1)
Combined tax (distributed)	~39.8%	Up to 37% (29.6% with QBI)
QBI deduction (IRC 199A)	Not available	20% on qualified business income
Payroll tax on distributions	No	No (but must pay reasonable salary)
SE tax on all income	No	No (only on salary)
QSBS exclusion (IRC 1202)	Yes (up to $10M excluded)	No
Stock classes	Unlimited	One class only
Number of shareholders	Unlimited	100 maximum
Foreign shareholders	Allowed	Not allowed
Retained earnings	Taxed at 21%	Taxed at individual rate (passed through)
Accumulated earnings tax	IRC 531: 20% penalty on excess accumulations	Not applicable
Personal holding company tax	IRC 541: 20% on undistributed PHC income	Not applicable

S-Corp eligibility requirements (IRC 1361):

Requirement	Details
Domestic corporation	Must be formed under U.S. state law
100 shareholders or fewer	Family members can count as one
Shareholders must be individuals, estates, or certain trusts	No corporations, partnerships, or LLCs as shareholders
U.S. citizens or residents only	No nonresident aliens
One class of stock	Voting and nonvoting OK, but same economic rights
Not an ineligible corporation	No banks (using IRC 585), insurance companies, DISCs, or certain financial institutions
Election	Form 2553 (must be filed by March 15 of the first S-Corp year, or within 2 months and 15 days of formation)

When is C-Corp better? When is S-Corp better?

Hypothetical example

Round numbers. For current guidance, see IRS S corporation guidance. Comparing a business with $500,000 net income under three scenarios.

Scenario 1: All profits distributed (owner needs the cash)

Item	C-Corp	S-Corp (non-SSTB)	S-Corp (SSTB)
Net income	$500,000	$500,000	$500,000
Corporate tax (21%)	($105,000)	$0	$0
Available for distribution	$395,000	$500,000	$500,000
QBI deduction (20% of QBI after the $150K salary)	N/A	($70,000)	$0 (SSTB, above threshold)
Taxable to owner	$395,000 (dividends)	$430,000	$500,000
Tax on distributions (23.8% qualified)	$94,010	N/A (already passed through)	N/A
Individual income tax	N/A	$159,100 (37% on $430K)	$185,000 (37% on $500K)
Salary FICA (S-Corp, $150K salary)	N/A	$22,950	$22,950
Total tax	$199,010	$182,050	$207,950
Winner		S-Corp (non-SSTB)	C-Corp wins by $8,940

Key findings:

S-Corp (non-SSTB) wins decisively when profits are distributed, because of the QBI deduction.
S-Corp (SSTB, no QBI) actually loses to C-Corp when all profits are distributed, because the combined 39.8% C-Corp rate is lower than the 37% S-Corp rate plus FICA, without the QBI offset.

Scenario 2: All profits retained (reinvested in growth)

Item	C-Corp	S-Corp (non-SSTB)
Net income	$500,000	$500,000
Corporate tax	($105,000)	$0
Retained in entity	$395,000	$500,000
Owner must pay on pass-through income	$0	$182,050 (personal tax on K-1 income)
Cash owner must fund from personal sources	$0	$182,050
Net available for reinvestment	$395,000	$317,950 ($500K - $182,050 owner tax)
Winner	C-Corp

When profits are retained, the C-Corp’s 21% rate is lower than the individual rate, and the owner does not face phantom income (taxed on income they did not receive). However, accumulated earnings tax (IRC 531) can apply if the C-Corp accumulates earnings beyond reasonable business needs.

Scenario 3: QSBS exit (founder selling in 5+ years)

Item	C-Corp (QSBS)	S-Corp
Business sold for	$10,000,000	$10,000,000
Owner’s basis	$100,000	$100,000
Gain	$9,900,000	$9,900,000
QSBS exclusion (IRC 1202)	$9,900,000 (within $10M limit)	N/A (not available for S-Corp)
Federal capital gains tax	$0	$9,900,000 x 23.8% = $2,356,200
Tax savings from QSBS	$2,356,200

For founders planning a significant exit, the QSBS exclusion is often the deciding factor in favor of C-Corp.

Decision framework:

Situation	Recommended	Why
Distributing most profits + non-SSTB	S-Corp	QBI + payroll tax savings; no double tax
Distributing most profits + SSTB (high income)	C-Corp or S-Corp	Close call; model both with actual numbers
Retaining all profits for growth	C-Corp	21% rate; no phantom income
Seeking venture capital	C-Corp	VCs require C-Corp structure; preferred stock
Planning exit via sale in 5+ years	C-Corp	QSBS exclusion ($10M+ tax-free)
Simple business, 1-2 owners, distributing	S-Corp	Simplest structure; avoid double tax
International shareholders or investors	C-Corp	S-Corp does not allow foreign shareholders
Real estate holding company	LLC (partnership)	Flexibility > S-Corp restrictions
Multiple classes of ownership	C-Corp or LLC	S-Corp allows only one class of stock

Converting between C-Corp and S-Corp:

C-Corp to S-Corp:

Item	Details
How	File Form 2553
Built-in gains tax	IRC 1374: 21% tax on built-in gains recognized within 5 years of conversion
E&P	Prior C-Corp E&P tracked; distributions from AAA (S-Corp earnings) first, then E&P
Passive investment income	IRC 1375: if passive income exceeds 25% of gross receipts and C-Corp E&P exists, excess is taxed

S-Corp to C-Corp:

Item	Details
How	Revoke S election (consent of shareholders holding > 50% of stock)
Effect	Immediate; entity taxed as C-Corp from revocation date
QSBS clock	Starts from the date of C-Corp status (5-year holding period begins)
Distribution ordering	Changes from S-Corp rules (AAA, then E&P, then capital) to C-Corp rules (E&P first)

State-level considerations:

State	S-Corp Tax	C-Corp Tax
California	1.5% entity-level tax (minimum $800)	8.84% (minimum $800)
New York	No entity-level S-Corp tax (but PTET available)	6.5%
Texas	Same franchise tax for both	Same franchise tax
Florida	No S-Corp tax	5.5%
Illinois	1.5% PTE tax (replacement for personal income tax)	9.5% (7% + 2.5% PPRT)

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

What salary rule comes with choosing an S-Corp?

An S-Corp owner who works in the business is a corporate officer, and officers are employees for payroll tax. The IRS says an S-Corp must pay a shareholder-employee reasonable compensation before making non-wage distributions, and it can reclassify distributions as wages if the salary is too low. That payroll cost belongs in the S-Corp column of any comparison.

How much is reasonable has no formula. The Code and regulations give no specific guideline, so the $150,000 salary in the example above is an assumption for the math. Courts weigh your training and experience, duties, time devoted, what comparable businesses pay for similar services, and other factors the IRS lists.

The salary also changes the QBI side of the comparison. Reasonable compensation isn’t qualified business income, so QBI is what’s left after your salary. Section 199A no longer expires after 2025, which makes that a lasting part of the S-Corp math.

What is a single-member LLC and how is it taxed?

A single-member LLC is a legal entity with one owner. The IRS treats it as a disregarded entity by default, meaning it does not file its own return; income and expenses flow directly to Schedule C on the owner’s personal Form 1040. The LLC provides liability protection without adding a separate tax return. Self-employment tax applies to all net income, same as a sole proprietorship. You can elect S-Corp taxation by filing Form 2553, which keeps the LLC legal structure while changing the tax treatment to require a reasonable salary and allowing the remaining profit as a distribution free of FICA. State treatment varies: some states charge an annual LLC fee or franchise tax regardless of federal tax election.

Related guides:

SaaS Entity Structure: LLC, S-Corp, or C-Corp for Software Companies

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Cite this page

Yarik Yarosh, CPA. "C-Corp vs. S-Corp: Complete Entity Selection Guide for Business Owners." Blue Cloud CPA, September 5, 2026, updated September 23, 2026. https://bluecloudcpa.com/guides/small-business-tax-planning-c-corp-vs-s-corp-entity-selection-comparison

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