If you’re doing consulting work on your own, the tax structure question usually shows up right after the first decent year. Not because the IRS suddenly got more interesting, but because you look at the money leaving your account and realize “simple” can get expensive.

This is the real tax structure for consultants problem: the wrong setup can leave you paying the full 15.3% self-employment tax on every dollar of business profit when you didn’t need to. The flip side is just as annoying. Plenty of people jump into an S-corp too early, add payroll, filings, and state fees, and save less than the paperwork costs them.

So the choice is not about sounding official. It’s about deciding when legal protection matters, when payroll complexity is worth it, and when state-level fees quietly eat the tax savings you thought you were getting.

Tax Structure for Consultants Starts With the 15.3% Self-Employment Tax

The biggest tax difference between structures is not some obscure deduction. It’s self-employment tax.

The IRS says the self-employment tax rate is 15.3%, split between 12.4% for Social Security and 2.9% for Medicare, and it’s applied to 92.35% of your net earnings from self-employment. For 2025, the Social Security portion applies up to $176,100 of net earnings, while the Medicare portion keeps going. The IRS also notes that an additional 0.9% Medicare tax can kick in above $200,000 for single filers.

Here’s why that matters: if you’re operating as a sole proprietor, or as a single-member LLC taxed the default way, your entire net profit is generally exposed to that self-employment tax. Make $80,000 in net business income and the whole amount is in the blast radius. That’s the starting point.

This is where a lot of advice gets sloppy. People talk about an LLC as if it changes your federal tax picture by itself. It doesn’t. Not by default. The LLC can matter for legal separation. For federal tax, the IRS usually treats a single-member LLC the same as a sole proprietorship unless you elect something different.

That one distinction explains most of the confusion. A lot of consultants are solving a tax problem with a legal tool, then wondering why the math didn’t move.

Sole Proprietorship vs. LLC: What You Actually Gain

An LLC can be useful. It just doesn’t do the thing many people assume it does.

Tax Foundation data shows pass-through businesses make up roughly 94% of U.S. firms, and sole proprietorships alone account for about 73% of that group. S-corporations make up about 13%, while partnerships come in around 8%. In other words, most business owners are already in pass-through territory. That’s not exotic. That’s normal.

What an LLC buys you first is liability separation. That’s the legal wrapper. If you sign contracts, work with clients directly, or want cleaner separation between personal and business activity, that can matter a lot.

What it does not automatically buy you is lower federal self-employment tax. For a single-member LLC, the default IRS treatment is still pass-through taxation, which means all net income still flows onto your return and is still generally subject to the full self-employment tax.

The state-level startup cost is usually manageable, but not trivial. Wolters Kluwer pegs average LLC filing fees at $132, with some states around $35 and others above $500. That does not make an LLC a bad idea. It just means the fee should buy something real, not mythology.

Put differently: an LLC is often a good legal housekeeping move. It is not, on its own, the magic tax switch. The real tax decision comes later, when you decide whether an S-corp election is worth the trouble.

When an S-Corp Election Starts Making Financial Sense

This is the part everyone cares about, because this is where the tax savings can become real.

Gusto notes that many tax professionals use a rough threshold of $60,000 to $80,000 in annual net business income before an S-corp election starts to make sense. The logic is simple. As an S-corp owner, you pay yourself a reasonable salary through payroll, and the remaining profit can come out as distributions. Those distributions are not subject to self-employment tax the way sole proprietor profit is.

Take a common example: $80,000 in net business income, with a $50,000 reasonable salary. That leaves $30,000 as distributions. Apply 15.3% to that $30,000 and the gross self-employment tax savings are about $4,590.

That sounds great until real life shows up with an invoice.

Payroll processing, Form 1120-S preparation, bookkeeping cleanup, and state compliance often add $1,000 to $2,000 a year, sometimes more. So the question is not “Can an S-corp save tax?” Yes, it can. The question is whether the net savings, after admin costs, still justify the structure.

Below about $60,000 in net income, the answer is often no. The savings are too thin, and the overhead starts wearing a fake mustache and calling itself strategy. Between $60,000 and $80,000, you’re in judgment-call territory. Above that, the math starts getting harder to ignore, especially if your state doesn’t pile on extra entity taxes.

The Reasonable Salary Rule Is Not Optional

The S-corp advantage only works if the salary side of the arrangement is defensible.

The IRS is explicit on this point. In Fact Sheet FS-2008-25, the agency says shareholder-employees of S-corporations must receive reasonable compensation before taking non-wage distributions. IRS Publication 15 also anchors payroll compliance around ordinary wage rules. In plain English, you cannot pay yourself $12,000 to do $100,000 worth of consulting work and pretend the rest is magically exempt from payroll tax.

What counts as reasonable depends on facts and circumstances: the work you do, your training, how much time you spend in the business, and what someone doing similar work would ordinarily be paid. That’s less tidy than a fixed formula, but the principle is obvious enough. If the salary looks absurdly low, it probably is.

Why does the IRS care? Because a lowball salary turns distributions into a payroll-tax dodge. If the IRS reclassifies those distributions as wages, you can end up owing back payroll taxes, interest, and penalties. That is an expensive way to learn that “my CPA said probably fine” is not a legal standard.

This doesn’t make S-corps dangerous. It makes them grown-up structures. You need records, a real payroll setup, and a salary you can explain without squirming.

State-Level Traps That Can Wipe Out the Savings

National tax advice has a bad habit of pretending every state is Nebraska. It isn’t.

California is the cleanest example. The California Franchise Tax Board says LLCs and S-corporations both face an $800 minimum franchise tax, and S-corporations also pay 1.5% of net income, subject to the minimum. So if you’re in California, your S-corp savings need to outrun not just payroll costs, but that franchise-tax floor too.

Now compare that with lighter-cost states. Wyoming and South Dakota can be far cheaper annually, and Texas does not impose franchise tax on entities under $1.23 million in revenue. That is a very different backdrop for the same federal S-corp election.

New York adds its own flavor of nonsense with LLC publication rules, which Wolters Kluwer says can cost roughly $500 to $1,500 depending on location. That’s not trivial, and it absolutely belongs in the math.

So take that earlier $80,000 example. In a low-fee state, an S-corp might still leave you meaningfully ahead after admin costs. In California, the $800 minimum tax plus payroll administration can shave a big chunk off the headline savings. That doesn’t kill the idea. It just means you should stop using generic internet advice and run your own numbers.

A Decision Framework for Solo Operators Over 50

Older consultants are not a niche in this conversation. They’re a major part of it.

AARP reported in February 2025 that self-employment rates are highest among workers 65 and older, at 23.4%. That lines up with reality: a lot of consulting businesses are built by experienced operators who got tired of corporate theater, layoffs, or both.

For that group, the structure decision has a few extra layers.

First, if your net business income is under roughly $60,000, a sole proprietorship or default-taxed single-member LLC is often the cleanest answer. You keep compliance simple, avoid payroll complexity, and probably don’t have enough spread for the S-corp to earn its keep.

Second, if you’re consistently in the $60,000 to $80,000-plus range, an S-corp deserves a serious look. But serious means serious. Factor in payroll service costs, tax-prep fees, state franchise taxes, and the time cost of dealing with a more formal setup.

Third, Social Security deserves attention if you’re still in your higher-earning years or claiming before full retirement age. Wages paid to you through an S-corp count as earned income. Distributions generally do not. That can matter because lower wages may affect future benefit calculations if you’re still building your 35-year earnings record, and earned-income rules matter differently if you’ve already claimed benefits early.

Fourth, don’t ignore the Section 199A qualified business income deduction. The IRS says the deduction applies to qualified business income, but the structure changes the mechanics. In a sole proprietorship, the whole eligible profit amount is part of the analysis. In an S-corp, wages paid to you reduce the pass-through profit that may qualify. That doesn’t automatically make one structure better. It just means the “S-corp saves taxes” slogan can miss an important offset.

The practical framework is straightforward:

Keep the sole proprietor or single-member LLC setup if income is modest and simplicity matters most.

Consider the S-corp once profit is high enough that the payroll-versus-distribution split creates meaningful net savings after compliance costs.

And if you’re over 50 and close enough to retirement that Social Security or long-range tax planning matters, don’t DIY the final call from a YouTube thumbnail with a man yelling next to a red arrow. Run the numbers with a tax professional who can model your income, your state, and your timing.

Frequently Asked Questions

Can I switch from sole proprietor to S-corp mid-year without penalties?

Usually yes, but timing matters. The IRS requires an S-corp election on Form 2553, and there are filing deadlines for when that election takes effect. Mid-year changes are possible, but they create partial-year bookkeeping issues and can complicate payroll setup. This is one of those cases where “possible” and “convenient” are not the same word.

If I’m a solo consultant, do I need both an LLC and an S-corp election?

Not necessarily. You can elect S-corp taxation without forming an LLC first if you use a corporation structure, but many solo consultants choose an LLC first for legal separation and then elect S-corp tax treatment. The key point is that the LLC and the S-corp election solve different problems: one is legal structure, the other is tax treatment.

How does my business structure affect Social Security benefits when I’m over 50?

The big distinction is wages versus distributions. Wages generally count as earned income and feed into payroll tax systems tied to Social Security. S-corp distributions generally do not. If you’re still replacing lower-earning years in your Social Security record, or if you’ve already claimed before full retirement age, that distinction can matter enough to include in the decision.

What happens if the IRS decides my S-corp salary is too low?

The IRS can reclassify some distributions as wages. If that happens, you may owe back payroll taxes, plus interest and penalties. That’s why IRS Fact Sheet FS-2008-25 matters so much. The tax break depends on paying a salary you can actually defend.

Do I need a registered agent, and what does that typically cost?

If you form an LLC or corporation, most states require a registered agent with a physical address in the state. Costs vary, but many commercial registered-agent services land somewhere around $100 to $300 a year. It’s usually not the largest cost in the structure decision, but it belongs on the checklist with filing fees, payroll costs, and annual tax prep.

The best structure for most consultants is not the most sophisticated one. It’s the one that leaves more after-tax income in your pocket without turning your business into a part-time compliance hobby.

For many solo operators, that means staying simple until profit levels clearly justify the S-corp move. When that moment comes, the math can work. But the math has to be your math, in your state, with your actual income.

Continue reading: Read the pillar — Making Money After 50

This article is for informational purposes only and is not financial advice. Consult a qualified professional for personalized guidance.