S-Corp Taxes for Beginners: How S Corporations Work and What You Need to Know
The S-corp gets its name from Subchapter S of the Internal Revenue Code. It’s not a type of business entity — it’s a tax election. You can be an LLC or a corporation under state law and then elect S-corp tax treatment with the IRS. The election changes how your business income is taxed at the federal level. Everything else about your entity — liability protection, management structure, state-law status — stays the same.
People hear about S-corp taxes and immediately think “tax savings,” which isn’t wrong, but it’s incomplete. The S-corp saves money in a specific way: it reduces self-employment tax on business income above a reasonable salary. If that sounds confusing, don’t worry. We’re going to break it down piece by piece. For a side-by-side comparison with LLC taxation, see our S-Corp vs. LLC comparison for freelancers.
How S-Corp Taxes Work: The Basics
An S corporation doesn’t pay federal income tax at the entity level. Instead, it files an informational return (Form 1120-S), and the income “passes through” to the shareholders, who report it on their personal tax returns via Schedule K-1. This is why S-corp taxes are described as “pass-through” taxation — the business income passes through the entity and gets taxed only once, at the individual level.
This is different from a C corporation, which pays its own corporate income tax on profits (currently 21% federal), and then shareholders pay tax again when those profits are distributed as dividends. That double taxation is the main reason most small businesses avoid C-corp status. S-corp taxes eliminate the double tax by moving all the taxation to the individual shareholder level.
Here’s where it gets interesting. An S-corp shareholder who also works in the business must take a “reasonable salary” paid through payroll. That salary is subject to payroll taxes: the employee pays 7.65% (Social Security at 6.2% and Medicare at 1.45%), and the S-corp pays a matching 7.65% as the employer. But any profit above the salary flows through as a distribution, and distributions are not subject to payroll taxes or self-employment tax. That’s the S-corp tax advantage in a sentence.
The Reasonable Salary Requirement
The IRS requires that S-corp shareholders who perform services for the corporation pay themselves a reasonable salary before taking distributions. “Reasonable” means comparable to what someone with your skills and experience would earn doing similar work in your geographic market. A software developer in New York City billing $300,000 through an S-corp can’t take a $30,000 salary and distribute the rest. The IRS would reclassify those distributions as wages, assess back payroll taxes, and add penalties.
There’s no bright-line rule for what constitutes reasonable. The IRS looks at factors like the nature of the services, the amount of time spent, comparable salaries for similar roles, the company’s revenue and profitability, and what employees in similar positions earn at other companies. We use Bureau of Labor Statistics data, industry compensation surveys, and historical salary precedents to set defensible salary levels for clients. For most service-based S-corps, a reasonable salary falls somewhere between 40% and 60% of net profits, though the exact percentage varies by situation.
A Real Example of How S-Corp Taxes Save Money
Let’s say your business earns $180,000 in net profit. Without the S-corp election (operating as a sole proprietorship or single-member LLC), the entire $180,000 is subject to self-employment tax. The SE tax on $180,000 is roughly $22,950 (after the 92.35% multiplier and accounting for the Social Security wage base).
With the S-corp election, you pay yourself a reasonable salary of $90,000. Payroll taxes on $90,000: the employee share is $6,885, and the employer share is another $6,885, for a total of $13,770. The remaining $90,000 passes through as a distribution with no payroll tax or SE tax. Your total payroll tax bill with the S-corp: $13,770. Without it: $22,950. That’s $9,180 in annual savings on S-corp taxes — or about $765 per month.
The income tax portion is roughly the same either way, because the total income reported on your personal return is identical. The savings come entirely from the payroll/SE tax side.
S-Corp Tax Filing Requirements
S-corp taxes require more paperwork than a sole proprietorship. The S-corp files Form 1120-S by March 15 each year (not April 15). This is an informational return that reports the company’s income, deductions, and each shareholder’s distributive share. Each shareholder receives a Schedule K-1 showing their piece of the income, which they then include on their personal Form 1040.
You also need to run payroll, which means filing quarterly payroll tax returns (Form 941), paying federal and state payroll tax deposits on time, issuing W-2s at year-end, and maintaining proper payroll records. Most S-corp owners use a payroll service like Gusto, ADP, or Paychex — the cost runs $40 to $150 per month for a single-employee S-corp.
Late filing penalties for S-corp taxes are steep: $235 per shareholder per month (2024 rate), up to 12 months. A single-shareholder S-corp that files two months late owes $470 in penalties. Multi-shareholder S-corps accumulate penalties even faster. File on time or file an extension (Form 7004) by March 15 — the extension gives you until September 15.
When S-Corp Taxes Don’t Make Sense
The S-corp election isn’t right for every business. If your net profit is below $40,000 to $50,000, the cost of running payroll, filing the 1120-S, and the additional accounting complexity can eat into the savings enough that you’re breaking even or losing money on the election. The payroll service costs $500 to $1,500 per year, and the 1120-S preparation adds $500 to $1,500 to your tax prep bill compared to a simple Schedule C. If your SE tax savings are only $2,000, you might be spending $2,000 on compliance to get there.
Businesses with irregular income also face challenges with S-corp taxes. The payroll needs to be consistent and paid regularly throughout the year. You can’t skip payroll for six months and then catch up in December with a lump-sum salary payment — the IRS expects regular, timely payroll processing. If your revenue is highly seasonal or unpredictable, managing the payroll cash flow adds complexity.
Real estate businesses with passive income are another poor fit. S-corp distributions don’t qualify for the lower self-employment tax rates on passive income, and the S-corp structure can complicate Section 199A (QBI deduction) calculations and limit the ability to specially allocate income and losses among owners.
Related Resources
Sources & References
- IRS — S Corporations overview
- IRS — About Form 1120-S, U.S. Income Tax Return for an S Corporation
- IRS — About Form 2553, Election by a Small Business Corporation
- 26 U.S.C. Subchapter S — Tax Treatment of S Corporations and Their Shareholders (Cornell LII)
- IRS — S Corporation Compensation and Medical Insurance Issues
Considering the S-Corp Election?
The Reed Corporation helps business owners evaluate whether S-corp taxes make sense, set reasonable salaries, and manage ongoing compliance.
Frequently Asked Questions
What are S-corp taxes and how do they differ from LLC taxes?
S-corp taxes are the federal tax obligations of a business that has elected S corporation status under Subchapter S of the Internal Revenue Code. The key difference between S-corp taxes and default LLC taxes is how self-employment tax applies to business profits. With a standard single-member LLC, your entire net profit is subject to self-employment tax at 15.3%. With S-corp taxes, only your salary (paid through payroll) is subject to payroll taxes — the remaining profit flows through as a distribution that avoids those taxes entirely.
Both structures are pass-through entities for income tax purposes, meaning the business income ends up on your personal Form 1040 either way. The income tax is the same. The difference with S-corp taxes is strictly on the employment tax side. An LLC owner earning $150,000 pays roughly $19,000 in self-employment tax on the full amount. An S-corp owner earning the same $150,000 who takes a $75,000 salary pays about $11,475 in payroll taxes (employer plus employee share on the salary), saving roughly $7,500 in S-corp taxes compared to the LLC structure.
The trade-off is complexity. S-corp taxes require a separate business return (Form 1120-S), payroll processing, quarterly payroll tax deposits, W-2 issuance, and compliance with the reasonable salary requirement. LLC taxes for a single-member LLC are reported on Schedule C — no separate return, no payroll, no W-2s. The S-corp adds $1,500 to $3,000 per year in administrative and accounting costs. If the payroll tax savings exceed those costs, S-corp taxes win. If they don’t, the simpler LLC structure is better.
There’s also a structural difference in how distributions work under S-corp taxes. S-corp distributions must be proportional to ownership. If you own 50% of an S-corp, you get 50% of every distribution — no special allocations. LLCs taxed as partnerships can allocate income and distributions differently from ownership percentages if the operating agreement allows it. This flexibility makes partnerships (and LLCs taxed as partnerships) more attractive for ventures where the owners want unequal profit sharing, carried interest arrangements, or special allocation of specific deductions.
One more distinction: S-corp taxes come with ownership restrictions. You can’t have more than 100 shareholders, shareholders must be U.S. citizens or residents (no foreign owners), and there can be only one class of stock. LLCs have none of these limitations. If you’re planning to bring in foreign investors, issue preferred equity, or grow beyond 100 owners, S-corp taxes aren’t available to you — you’d need to consider partnership or C-corp treatment instead.
How much does an S-corp save on taxes compared to a sole proprietorship?
The savings from S-corp taxes depend on your net profit level and what constitutes a reasonable salary for your role. The savings come exclusively from reduced self-employment/payroll taxes on the portion of income treated as distributions rather than salary. At lower profit levels, the savings are small or nonexistent. At higher levels, they can be substantial — $10,000 to $20,000 per year or more.
Let’s walk through three scenarios to show how S-corp taxes compare. At $60,000 in net profit, a sole proprietor pays about $8,478 in SE tax. An S-corp owner taking a $45,000 salary pays about $6,885 in total payroll taxes (employer plus employee). The S-corp taxes savings: roughly $1,593. After accounting for $1,500 to $2,500 in additional accounting and payroll costs, you’re barely breaking even or slightly behind. This is why we typically don’t recommend the S-corp election below $50,000 in profit.
At $120,000 in net profit, the math shifts. A sole proprietor pays about $16,956 in SE tax. An S-corp owner with a $65,000 salary pays about $9,945 in payroll taxes. The S-corp taxes savings: roughly $7,011. Subtract $2,000 in added compliance costs, and you’re netting about $5,000 per year in real savings. That’s meaningful — enough to fund a retirement contribution, hire a contractor, or simply keep more of what you earn.
At $250,000, the savings from S-corp taxes become hard to ignore. A sole proprietor pays roughly $28,000 in combined SE tax (including the additional Medicare tax). An S-corp owner with a $110,000 salary pays about $16,830 in payroll taxes. The savings: over $11,000 per year before accounting for compliance costs. After costs, you’re netting $9,000 or more annually. Over five years, that’s $45,000 in reduced S-corp taxes — enough to buy a car or make a meaningful dent in a mortgage.
These numbers are approximations, and your specific situation will vary based on your state (some states have additional S-corp taxes or fees), your filing status, and where your income falls relative to the Social Security wage base ($168,600 for 2024). Once your salary exceeds the wage base, only the Medicare portion (2.9% plus the 0.9% additional Medicare tax) applies to wages above that threshold, which reduces the incremental savings. A CPA can run the exact comparison for your situation in about 30 minutes using your actual numbers. If you’re earning $60,000 or more through a sole proprietorship or single-member LLC, the analysis is worth doing.
What is a reasonable salary for S-corp taxes?
A reasonable salary for S-corp taxes is the amount you’d realistically earn performing the same work as an employee at a comparable company. The IRS doesn’t publish a specific formula or percentage — they evaluate reasonableness based on the facts of each case. Factors include the nature of your services, the time you dedicate to the business, comparable salaries for similar roles in your industry and geographic area, the corporation’s revenue and profitability, and the relationship between salary and total distributions.
In practice, most S-corp owners set their reasonable salary somewhere between 40% and 60% of net profits, though that range isn’t a rule — it’s a pattern we observe across clients. A marketing consultant in New York City earning $200,000 through their S-corp might set a salary of $95,000 to $110,000, based on what comparable marketing directors earn in the NYC market. A plumber earning $200,000 might set a salary of $75,000 to $85,000, because plumber salaries are lower than marketing director salaries even though the business profits are identical.
The IRS has won court cases against S-corp owners who set unreasonably low salaries to minimize S-corp taxes. In one well-known case (Watson v. Commissioner), an accountant earning $200,000+ through his S-corp paid himself a salary of $24,000. The Tax Court ruled the salary was unreasonable and reclassified distributions as wages, assessing back payroll taxes plus penalties. The takeaway: the salary has to pass the straight-face test. If you couldn’t defend your salary to an IRS agent without squirming, it’s too low.
We set reasonable salaries for S-corp taxes using a combination of Bureau of Labor Statistics wage data, industry compensation surveys (Robert Half, Glassdoor, Salary.com), and the client’s actual time commitment. If you’re working 60 hours a week in your business, your salary should reflect full-time-plus compensation for someone with your skills. If you’re working 15 hours a week and the business runs mostly on contractor labor, a lower salary is defensible because your personal contribution is proportionally smaller.
One thing worth noting: the reasonable salary for S-corp taxes doesn’t have to stay the same every year. As your business grows, your salary should grow too. If you’ve been paying yourself $60,000 for three years while profits doubled from $100,000 to $200,000, the IRS might question why your compensation didn’t keep pace with the company’s growth. We typically review and adjust salary levels annually as part of our year-end tax planning process, making sure the number stays defensible as the business evolves.
When is the S-corp tax return due and what forms do I file?
S-corp taxes are reported on Form 1120-S, which is due by March 15 of the year following the tax year. For the 2025 tax year, the filing deadline is March 15, 2026. This is earlier than the individual tax return deadline (April 15), because the S-corp return generates the Schedule K-1s that shareholders need to complete their personal returns. If the S-corp filed late, the shareholders wouldn’t have their K-1s in time to file their own 1040s.
You can request a six-month extension by filing Form 7004 by March 15, which extends the S-corp taxes filing deadline to September 15. The extension is automatic — you don’t need IRS approval. But like individual extensions, it only extends the time to file, not the time to pay. If the S-corp owes any tax (which is rare but possible in certain states or with built-in gains), payment is still due by March 15.
Beyond the annual Form 1120-S, S-corp taxes involve quarterly payroll filings. You file Form 941 every quarter (due by the last day of the month following the quarter end: April 30, July 31, October 31, January 31) reporting wages paid, employment taxes withheld, and the employer’s share of FICA taxes. You also make federal tax deposits either semi-weekly or monthly, depending on the size of your payroll — most single-employee S-corps are monthly depositors.
At year-end, S-corp taxes require issuing W-2s to all shareholder-employees by January 31 and filing Form W-3 (the transmittal summary) with the Social Security Administration. If the S-corp paid any contractors $600 or more, you also need to file 1099-NEC forms. And don’t forget state filings — most states require a state-level S-corp return or a composite return, with deadlines that vary by state.
The penalty for late S-corp taxes filings is $235 per shareholder per month for up to 12 months. For a two-shareholder S-corp that files three months late, that’s $1,410 in penalties. The IRS does offer first-time penalty abatement if you have a clean compliance history for the prior three years, and there’s also a Revenue Procedure (Rev. Proc. 2013-30) that provides automatic relief for certain late S-corp elections. But the easiest path is filing on time. Set a reminder for March 1 to start your S-corp taxes preparation, and either file the return or the extension by March 15.
Can any business elect S-corp tax treatment?
Not every business qualifies for S-corp taxes. The IRS imposes several eligibility requirements that must be met both at the time of election and continuously throughout the life of the S-corp. Break any of these rules and the IRS can terminate your S-corp election retroactively, which creates a tax mess that’s expensive to clean up.
The ownership rules are the biggest filter. To elect S-corp taxes, the business can have no more than 100 shareholders. All shareholders must be U.S. citizens or resident aliens — no foreign owners allowed. Shareholders must be individuals, certain trusts, or estates — other corporations, partnerships, and most LLCs cannot own shares in an S-corp. And the company can have only one class of stock, meaning all shares must have identical rights to distributions and liquidation proceeds (though voting rights can differ).
These restrictions eliminate certain business structures from S-corp taxes entirely. If you’re planning to raise capital from a venture fund (which is typically organized as a partnership or LLC), the fund can’t be an S-corp shareholder. If one of your co-founders is a non-resident alien, S-corp taxes are off the table. If you want to issue preferred stock with different distribution rights than common stock, you can’t do it in an S-corp without violating the single-class-of-stock rule.
The entity type doesn’t matter much. Both corporations and LLCs can elect S-corp taxes. A C corporation converts to S-corp status by filing Form 2553 with the IRS. An LLC elects S-corp treatment by filing Form 2553 (and in some cases Form 8832 first, to elect corporate classification before electing S status, though the IRS now accepts a single Form 2553 filing for LLCs in most cases). The election must be filed by March 15 of the year you want it to take effect, or within 75 days of forming the entity.
Late elections are possible through IRS relief procedures. If you missed the March 15 deadline, you can still request a late S-corp election by filing Form 2553 with a reasonable-cause statement. The IRS grants late election relief fairly routinely — especially for new businesses that didn’t know about the deadline. Revenue Procedure 2013-30 provides an automatic approval process for certain late elections, and even outside that procedure, the IRS approves most reasonable-cause requests. We’ve filed late S-corp elections for clients that were granted retroactively to the beginning of the tax year, saving them a full year of self-employment tax they would have owed under default LLC taxation. If you think S-corp taxes might save you money but you’ve already passed the deadline, it’s worth asking your CPA whether a late election is still viable.