Most small business owners form an LLC because it is simple, flexible, and inexpensive to set up. What many do not realize is that a single-member LLC is taxed exactly like a sole proprietor by default: every dollar of net profit is subject to both income tax and self-employment tax. When your net profit is low, this is fine. When it crosses a certain threshold, you are leaving significant money on the table every year.
The S-corporation election is the primary mechanism for changing that. Understanding when it makes sense, how the math works, and what the administrative overhead actually looks like is one of the most valuable tax planning conversations a growing business owner can have.
How a Single-Member LLC Is Taxed by Default
A single-member LLC is a disregarded entity for federal tax purposes. The IRS treats it as if it does not exist separately from you. All net profit from the business flows directly to your personal tax return and is subject to two taxes: income tax (at your marginal rate) and self-employment tax.
Self-employment tax is 15.3% on the first $168,600 of net self-employment income in 2024 (this threshold adjusts annually for inflation), and 2.9% on net income above that amount. This is the combined employee and employer share of Social Security and Medicare taxes. As an employee, your employer pays half; as a self-employed person, you pay the full amount. You do get a deduction for half of the SE tax you pay, which slightly reduces the impact, but the headline rate is 15.3% on every dollar of net profit up to the wage base.
On $150,000 in net profit, your self-employment tax is approximately $21,227 before the above-the-line deduction for half of SE tax.
How an S-Corp Changes the Tax Treatment
An S-corporation is a federal tax election, not a business entity type. You can elect S-corp status as an LLC or as a corporation. The election changes how your income is classified and therefore how much of it is subject to payroll taxes.
With an S-corp election, you are required to pay yourself a reasonable salary for the work you do in the business. That salary is subject to payroll taxes -- the same Social Security and Medicare taxes as self-employment tax, at the same rates. But profit above and beyond your reasonable salary passes through to you as an S-corp distribution. Distributions are not subject to self-employment tax or payroll taxes.
The tax savings come from that distinction. If your reasonable salary is $80,000 and your net profit is $150,000, you pay payroll taxes on $80,000. The remaining $70,000 passes through as a distribution, subject only to income tax, not to payroll taxes. That saves you approximately $10,710 in payroll taxes in this scenario.
The Math at Different Income Levels
The savings from an S-corp election scale with the gap between your reasonable salary and your net profit. Here is an approximation of the tax savings at different income levels, assuming a reasonable salary set at roughly half of net profit:
- $100,000 net profit: Reasonable salary $60,000. Distribution $40,000. SE tax savings approximately $5,800. Annual accounting and payroll overhead approximately $2,000 to $4,000. Net benefit marginal at this income level -- the crossover point depends heavily on state costs and accounting fees.
- $150,000 net profit: Reasonable salary $80,000. Distribution $70,000. SE tax savings approximately $10,710. Net benefit after administrative costs is typically $6,000 to $8,000 per year. This is where the election becomes clearly worthwhile for most business owners.
- $200,000 net profit: Reasonable salary $100,000. Distribution $100,000. SE tax savings approximately $15,300. Net benefit after administrative costs is typically $11,000 to $13,000 per year. At this income level, the election is almost always worthwhile if you qualify.
The crossover point -- where the tax savings exceed the administrative costs -- is typically somewhere between $50,000 and $80,000 in net profit, depending on your state and your accounting fees. Below that threshold, the savings do not justify the overhead. Above it, the question shifts from whether to make the election to when.
The Reasonable Salary Requirement
The IRS requires S-corp owner-employees to pay themselves a salary that is comparable to what they would pay an employee to do the same work. This is one of the most audited areas for small businesses. The IRS looks at industry compensation data, the owner's qualifications, the time spent on the business, and the services actually performed.
Paying yourself $1 per year in salary while taking $200,000 in distributions is not a strategy. It is an audit trigger. The salary needs to be defensible. A tax advisor can help you identify the right salary for your industry and role -- one that is legitimate enough to withstand scrutiny and set at a level that still produces meaningful tax savings.
Administrative Overhead of S-Corps
An S-corp election comes with real administrative requirements that do not exist for a single-member LLC taxed as a disregarded entity:
- Payroll processing: You need to run payroll, withhold taxes, and remit payroll taxes on your salary. This requires a payroll service or software. Cost: $500 to $1,500 per year for a basic payroll service.
- Quarterly payroll filings: You file Form 941 quarterly with the IRS and your state's equivalent. Your payroll service typically handles this, but it adds compliance obligations.
- Annual corporate tax return: An S-corp files Form 1120-S in addition to your personal return. This is more complex than a Schedule C and typically costs more to prepare.
- Higher accounting fees: Most CPAs and accounting firms charge more to prepare an S-corp return than a sole proprietor or single-member LLC return. Expect $500 to $1,500 more per year.
Total additional overhead: typically $2,000 to $4,000 per year. This is the denominator in your cost-benefit calculation.
State-Specific Considerations
Federal tax law treats S-corps one way. States do not have to follow suit, and several impose additional costs or restrictions:
- California: Charges an additional 1.5% franchise tax on S-corp net income, with a minimum of $800 per year. At lower income levels, this meaningfully reduces the federal savings.
- New York: Has its own S-corp filing requirements and a fixed-dollar minimum tax that scales with federal S-corp income.
- Some states do not recognize S-corp elections: A handful of states tax S-corps at the entity level, which can eliminate the savings entirely in those states.
Before making the election, verify how your state treats S-corp income. A tax advisor in your state can model the combined federal and state savings so you have an accurate picture.
When to Make the S-Corp Election
The timing of the election matters. To have an S-corp election effective for a given tax year, you generally need to file Form 2553 within 75 days of the beginning of that tax year (or within 75 days of formation for a new business). Late elections are possible in some circumstances, but it is better to plan ahead.
The decision framework is simple: if your net profit is consistently below $50,000, the election is likely not worth the overhead. If it is consistently above $80,000, the election is almost certainly worth evaluating. Between those numbers, run the specific math for your situation, your state, and your current accounting costs.
The Role of a Tax Advisor in This Decision
The S-corp vs. LLC decision is not one to make based on a blog post, including this one. The right answer depends on your specific income level, your state of formation, your accounting relationship, your projections for the next few years, and whether there are other planning strategies that should be prioritized first. A tax advisor can model the actual after-tax savings for your situation in a single session.
Read the full tax planning context in The Complete Guide to Tax Planning for Business Owners. When you are ready to evaluate your entity structure with a qualified professional, find vetted tax advisors at Expert Sapiens Tax Advisory.
