Most business owners believe picking between an LLC S Corp and C Corp is a legal decision they make once and forget. That belief costs California entrepreneurs tens of thousands of dollars every single year. The truth is that your entity choice is the single biggest tax lever you control, and the wrong pick means you hand money to the IRS and the Franchise Tax Board that you never had to give up.

Here is the part nobody tells you: the “best” structure is not fixed. A sole proprietor pulling $40,000 in profit and a consultant clearing $180,000 should almost never use the same setup. This guide breaks down exactly how each structure is taxed, where the savings hide, and how to know when it is time to switch.

Quick Answer: How LLC, S Corp, and C Corp Taxes Actually Differ

An LLC by default is a pass-through entity, meaning all profit flows to your personal return and gets hit with self-employment tax of 15.3 percent on top of income tax. An S Corp is also a pass-through, but it splits your income into salary and distributions, so you only pay that 15.3 percent on the salary portion. A C Corp pays a flat 21 percent corporate tax, then taxes you again when profits leave as dividends, which is the famous double taxation problem.

For most profitable small businesses in California, the S Corp election wins on federal self-employment tax savings. But the answer shifts fast once you factor in profit level, health insurance, retained earnings, and California’s own fees.

Understanding the LLC S Corp and C Corp Tax Structures

Before you can pick the right one, you need to understand what each entity actually does to your money. These are three genuinely different tax animals, even though people talk about them like they are interchangeable options on a dropdown menu.

The LLC: Simple, Flexible, and Often Overtaxed

A Limited Liability Company (in plain English: a legal shell that separates your personal assets from business debts) is the default choice for new business owners because it is cheap to form and easy to run. But here is the catch most people miss. An LLC is not a tax classification at all. The IRS ignores the LLC label and taxes you as a sole proprietor if you are solo, or as a partnership if you have partners.

That means every dollar of net profit gets hit with self-employment tax. According to the IRS self-employment tax guidance, this runs 15.3 percent, covering Social Security and Medicare. So a freelancer with $90,000 in net profit pays roughly $12,717 in self-employment tax before income tax even enters the picture. Want to see your own number? Run your profit through this self-employment tax calculator to see exactly what you are exposed to.

The S Corp: The Self-Employment Tax Shield

An S Corp is not an entity you form. It is a tax election you make, usually on top of an existing LLC or corporation, by filing Form 2553. The magic is in how it treats your income. You become an employee of your own business and pay yourself a reasonable salary. That salary is subject to payroll taxes. Everything left over comes out as a distribution, which is not subject to self-employment tax at all.

Take that same business earning $90,000. If you pay yourself a reasonable salary of $50,000 and take $40,000 as a distribution, you only pay the 15.3 percent on the $50,000 salary. That is roughly $4,300 in self-employment tax savings in a single year. For a deeper look at the mechanics, our complete guide to S Corp tax strategy in California walks through every step.

The C Corp: Double Taxation With Hidden Upside

A C Corp is the default corporate structure, and it is a completely separate taxpayer from you. It files its own return and pays a flat 21 percent federal corporate tax on profits. The downside is double taxation. When the corporation pays you dividends, you pay tax again on your personal return. For a small operator, this usually feels like paying twice for the privilege of running your own business.

But C Corps are not villains. They shine for businesses that reinvest heavily, plan to raise venture capital, or want to offer robust fringe benefits. The ability to retain earnings inside the company at 21 percent, rather than passing everything through to a personal return that might sit in a 37 percent bracket, is a legitimate strategy for fast-growing firms.

The Self-Employment Tax Math That Changes Everything

The single biggest reason business owners switch from a default LLC to an S Corp is self-employment tax. This is where the real money lives, and it is where most people leave savings on the table for years without realizing it.

Let me show you the actual math with three profit levels so you can see where the switch starts paying off.

• $45,000 in profit: As an LLC, you pay about $6,358 in self-employment tax. An S Corp with a $30,000 salary drops that to about $4,590, saving roughly $1,768. After payroll and filing costs, the net win is modest.
• $95,000 in profit: LLC self-employment tax runs about $13,423. An S Corp with a $55,000 salary cuts it to about $8,415, a savings of over $5,000 before considering the extra compliance cost.
• $180,000 in profit: This is where it gets serious. An S Corp with an $95,000 salary can save $8,000 to $10,000 per year in self-employment tax alone.

Many business owners discover they crossed the profitable threshold years ago and simply never restructured. That is real money that went to the government instead of their retirement account or growth budget.

Pro Tip: The rough rule of thumb is that once your net profit clears $50,000 to $60,000 consistently, the S Corp election usually starts producing meaningful net savings after accounting for payroll and tax prep costs.

KDA Case Study: Consultant Saves $9,200 by Restructuring

Meet David, a marketing consultant in San Diego operating as a single-member LLC. He came to us clearing $165,000 in net profit and getting crushed by self-employment tax. On his default LLC setup, he was paying roughly $20,400 in self-employment tax every year, and it was quietly draining his ability to invest back into his business.

When David walked through his numbers with us, he had never even heard the phrase “reasonable salary.” He assumed his accountant would have flagged the opportunity, but his prior preparer only filed returns and never advised on structure. This is one of the most common and expensive gaps we see.

Our team ran a compensation study and set his reasonable salary at $92,000, which was defensible based on market rates for his role and industry. The remaining $73,000 flowed out as distributions, free of self-employment tax. We filed his Form 2553 S Corp election, set up compliant payroll, and adjusted his estimated payments accordingly.

The result: David saved approximately $9,200 in his first year on self-employment tax alone. He paid roughly $3,200 for the entity restructuring, payroll setup, and ongoing advisory. That is a 2.9x first-year return, and the savings repeat every year he stays in this structure. He also picked up a cleaner path to a solo 401(k) with higher contribution room tied to his W-2 wages.

Ready to see how we can help you? Explore more success stories on our case studies page to discover proven strategies that have saved our clients thousands in taxes.

LLC vs S Corp vs C Corp: Side-by-Side Comparison

Here is a clean breakdown of how the three structures stack up on the factors that matter most to your wallet.

The table tells the quick story, but the real decision depends on your specific numbers. Our entity formation services help you match the structure to your actual financial picture instead of guessing.

Why Most Business Owners Miss the S Corp Election

This is the section that saves people the most money, because the mistake is so common and so silent. The IRS does not send you a letter saying “you are overpaying self-employment tax, please elect S Corp status.” It simply collects the money.

The most frequent trap is timing. To have your S Corp election apply for the current tax year, you generally need to file Form 2553 within two months and 15 days of the start of that tax year. Miss that window and you are usually stuck with default taxation until next year, though relief provisions exist for reasonable cause. That single missed deadline can cost thousands.

The second trap is the reasonable salary rule. Some owners get greedy and pay themselves a tiny salary to shrink payroll tax. The IRS watches this closely, and an unreasonably low salary is one of the fastest ways to trigger an audit and penalties. The fix is simple: document a defensible salary based on your role, industry, and market rates.

Red Flag Alert: Paying yourself a $12,000 salary while taking $150,000 in distributions is not a strategy. It is an invitation for the IRS to reclassify your distributions as wages and hit you with back taxes and penalties.

California-Specific Considerations You Cannot Ignore

California adds a layer that generic online advice completely ignores, and it can flip the math. If you run a business in the state, these costs are non-negotiable and they affect which structure actually makes sense.

The Annual Franchise Tax and LLC Fee

Every LLC in California owes an $800 annual franchise tax through Form 3522, regardless of profit. On top of that, LLCs with gross receipts over $250,000 owe an additional gross receipts fee that scales with revenue. An S Corp also owes the $800 minimum but is subject to a 1.5 percent state tax on net income instead of the gross receipts fee. This distinction matters enormously for high-revenue, lower-margin businesses.

When California Fees Change the Answer

Consider a business with $1.2 million in gross receipts but only $80,000 in profit. As an LLC, the gross receipts fee alone could run around $6,000, on top of self-employment tax. As an S Corp, the 1.5 percent tax applies to net income, which is far smaller. Running the state-level comparison is essential, and it is exactly the kind of analysis our tax planning services handle so you do not overpay Sacramento.

This information is current as of July 26, 2026. Tax laws change frequently. Verify updates with the IRS or FTB if reading this later.

What If My Business Is Not Profitable Yet?

If your business is still in the startup phase or running at a loss, the default LLC is almost always the right call. There is no self-employment tax on losses, so the S Corp savings do not exist yet. Running payroll and paying for extra tax prep when you have no profit to shield just adds cost with no benefit.

Keep it simple while you grow. Track your net profit quarterly, and the moment you see it consistently clearing that $50,000 to $60,000 range, that is your signal to revisit the S Corp election with a professional.

How Do I Actually Switch to an S Corp?

Switching is more approachable than most owners expect. Here is the step-by-step path.

1. Confirm your entity is eligible. You need a qualifying LLC or corporation with allowable shareholders (generally U.S. individuals, under 100 shareholders).
2. Determine a reasonable salary. Base it on market data for your role, region, and industry. Document your reasoning.
3. File Form 2553. Submit it within the deadline window to elect S Corp status for the desired tax year.
4. Set up compliant payroll. You must actually run payroll and issue yourself a W-2, with proper withholding and quarterly filings.
5. Adjust your estimated taxes. Your tax picture changes, so update your quarterly payments to avoid underpayment penalties.

The IRS Form 2553 instructions spell out the eligibility rules and deadlines in detail.

Frequently Asked Questions

Can an LLC be taxed as an S Corp?

Yes, and this is one of the most powerful and underused strategies available. Your business keeps its LLC legal structure and liability protection while filing Form 2553 to be taxed as an S Corp. You get the best of both worlds: LLC simplicity and S Corp self-employment tax savings.

Is a C Corp ever the right choice for a small business?

Yes, when you plan to reinvest most profits into growth, raise venture capital, or offer significant tax-advantaged fringe benefits. The 21 percent flat corporate rate can beat a high personal bracket for retained earnings. But for the typical service business that distributes profits to the owner, double taxation usually makes it the wrong pick.

What happens if I pay myself too low a salary as an S Corp?

The IRS can reclassify your distributions as wages, then hit you with back payroll taxes, interest, and penalties. Unreasonably low compensation is a well-known audit trigger. Always set a defensible salary grounded in market data.

Do I have to change my structure every year?

No, but you should review it annually. As your profit grows, the optimal structure changes. What made sense at $40,000 in profit is rarely optimal at $200,000. An annual check-in ensures you are never overpaying.

The bottom line is this: the IRS is not hiding these structures from you. You just were never taught how to compare them properly. Choosing between an LLC, S Corp, and C Corp is not a one-time legal formality. It is a recurring financial decision that can save or cost you thousands every year.

Stop Overpaying on Self-Employment Tax This Year

If you are running a profitable business on a default LLC, there is a strong chance you are handing the IRS thousands of dollars you never owed. Our strategy team will run the exact LLC versus S Corp versus C Corp numbers for your situation, set a defensible salary, and map out your switch step by step. Book your consultation now and find out how much your current structure is costing you.