An LLC taxed as an S corporation can save employment taxes when business profit consistently exceeds a defensible owner salary by enough to cover payroll and compliance costs. A default-taxed LLC often costs less to operate when profits are modest or unpredictable. The best choice depends on your work, other wages, state taxes, and deductions—not a universal income threshold.
LLC vs. S-corp is a tax election, not just an entity choice
An LLC is a legal entity formed under state law. An S corporation is a federal tax classification that an eligible LLC or corporation can elect. Your business can therefore be both an LLC and an S corporation: an LLC legally, with S-corp treatment for federal taxes.
By default, a domestic single-member LLC is generally disregarded for federal income tax purposes. An individual owner operating a business usually reports its activity on Schedule C. A domestic LLC with multiple members generally files as a partnership unless it elects corporate treatment.
For the broader ownership and entity comparison, start with our LLC, S-Corp or Partnership entity choice tax guide. Here, we focus on an owner-operated business comparing default LLC taxation with an S-corp election.
How the taxes compare
| Issue | Default-taxed LLC | LLC taxed as an S corporation |
|---|---|---|
| Federal income tax | Profit generally passes through to owners | Profit generally passes through to shareholders |
| Owner employment taxes | Active business earnings generally face self-employment tax | Owner wages face payroll taxes; pass-through profit generally does not |
| Owner compensation | Sole proprietor takes draws, not W-2 wages | Working shareholder generally needs reasonable W-2 compensation |
| Main federal filings | Schedule C and Schedule SE, or Form 1065 and Schedules K-1 | Form 1120-S, Schedules K-1, and payroll returns |
| Administration | Usually simpler for a single owner | Payroll, salary support, basis tracking, and additional compliance |
| Ownership flexibility | Partnership taxation can allow flexible economic arrangements | Eligible shareholders and one class of stock required |
Partnership self-employment tax treatment requires separate analysis. Do not assume an active LLC member escapes that tax simply because state law provides limited liability.
Where S-corp tax savings come from
A sole proprietor generally pays self-employment tax on 92.35% of net business earnings. The headline rate is 15.3%: 12.4% Social Security, up to the applicable annual wage base, plus 2.9% Medicare. Additional Medicare tax can apply above filing-status thresholds, and wages from another job affect the calculation.
An S corporation pays its working owner wages subject to payroll taxes. Remaining pass-through business profit generally is not subject to self-employment tax. However, that profit remains subject to income tax, whether it is distributed or retained in the business.
The opportunity is therefore to reduce employment taxes on profit above reasonable compensation—not to make business income tax-free. Our guide to legally reducing self-employment tax explains why a zero-salary strategy is not a safe shortcut.
Worked example: $100,000 before owner compensation
Assume a single owner has $100,000 of profit before owner wages, employer payroll taxes, or incremental S-corp costs. A documented market salary is $60,000. Assume no other wages, earnings below the Social Security wage base, and no Additional Medicare tax.
- Default LLC: $100,000 × 92.35% × 15.3% produces approximately $14,130 of self-employment tax.
- S-corp wages: $60,000 × 15.3% produces $9,180 of combined employer and employee Social Security and Medicare taxes.
- Remaining S-corp profit: $100,000 − $60,000 − $4,590 employer payroll tax = $35,410 before incremental administrative costs.
- Gross employment-tax difference: approximately $4,950.
If incremental annual payroll, tax preparation, and bookkeeping costs total $2,500, roughly $2,450 remains before income-tax effects, unemployment taxes, and state differences. This is an initial screening calculation, not a complete tax projection. The deductible employer payroll tax and deductible portion of self-employment tax differ, and qualified business income deductions may change.
What is the break-even profit threshold?
There is no IRS rule saying an S-corp election becomes worthwhile at $50,000, $75,000, or $100,000 of profit. The useful threshold is the spread between sustainable profit and reasonable owner compensation, measured against the additional costs.
For contrast, assume $70,000 of profit and the same defensible $60,000 salary. Default LLC self-employment tax would be approximately $9,891, versus $9,180 of combined Social Security and Medicare taxes on S-corp wages. That roughly $711 difference would not cover $2,500 in incremental annual costs.
A business earning $180,000 with a supportable $80,000 owner salary may have a stronger case. But a highly specialized solo professional whose services generate nearly all revenue may need substantially higher compensation. We model at least a conservative year and an expected year before recommending an election.
Reasonable compensation: the number you must defend
The IRS does not provide a universal salary-to-distribution percentage. A 60/40 split is not a safe harbor. Reasonable compensation depends on duties, time worked, experience, location, comparable pay, and how the business generates revenue.
Prepare a compensation file before setting payroll:
- A written description of the owner's production, management, sales, and administrative responsibilities.
- Estimated hours by role and records supporting part-time or seasonal work.
- Relevant wage surveys, recruiting data, or comparable job postings.
- An explanation of revenue attributable to employees, equipment, intellectual property, or capital rather than solely to the owner.
- A dated salary decision and annual review when duties or profitability change.
Distributions cannot replace wages for services. If payroll is understated, the IRS can reclassify payments as wages and assess employment taxes, penalties, and interest.
Income-tax factors that can change the answer
Qualified business income deductions
Both structures may qualify for the Section 199A qualified business income deduction, subject to current-year rules and limitations. S-corp owner wages are not qualified business income, and employer payroll taxes reduce business profit. A payroll-tax reduction can therefore be partly offset by a smaller QBI deduction. At higher incomes, wage limitations can make the interaction more complicated.
Other wages, benefits, and state taxes
If your outside W-2 job already reaches the Social Security wage base, default LLC income may avoid the Social Security portion of self-employment tax. An S corporation still generally owes its own employer Social Security tax on its wages. Excess employee withholding may be creditable, but that does not eliminate the corporation's employer share.
Retirement contributions generally depend on earned compensation, not S-corp distributions. More-than-2% shareholder health insurance also has special payment and W-2 reporting requirements. States may impose S-corp taxes, minimum fees, or separate elections; pass-through entity tax elections can further change the result. Rules change, so confirm figures and requirements for the current tax year.
How to make and maintain the election
- Confirm eligibility. An S corporation generally must be domestic, have no more than 100 shareholders, have only eligible shareholders, and have one class of stock. Nonresident alien shareholders are generally prohibited.
- Review governing documents. An LLC operating agreement written for partnership taxation may contain distribution or liquidation provisions incompatible with S-corp status.
- File Form 2553. The usual deadline is no later than two months and 15 days after the beginning of the tax year the election should cover, or during the preceding tax year. A calendar-year election is commonly due March 15, adjusted for weekends and holidays. Late-election relief may be available.
- Establish payroll. Arrange deposits, generally Form 941 quarterly filings, Form 940 when required, W-2/W-3 reporting, and state compliance. An eligible LLC's timely Form 2553 generally also supplies the necessary corporate classification election; Form 8832 is not always separately required.
- Maintain annual records. File Form 1120-S and shareholder K-1s, track stock and debt basis, document distributions, and file Form 7203 when required.
Our checklist on whether your LLC should be taxed as an S corporation helps connect these requirements to an existing business.
Where this goes wrong
The most common mistake is comparing self-employment tax with owner payroll taxes while ignoring everything else. Other problems include unsupported salaries, missed payroll deposits, personal expenses booked as deductions, and distributions exceeding shareholder basis. Cash available in the bank is not proof that a distribution is tax-free.
Changing an existing partnership-taxed LLC also requires attention to liabilities, asset basis, ownership rights, and potential conversion taxes. Revoking an election later can create complications and restrictions on reelecting. Make the decision from a multiyear projection, not a single strong month.
Choose based on net savings, not the label
At SWITCH, our team pairs a CPA and a tax attorney on every file to evaluate salary support, federal and state taxes, and compliance costs. SWITCH is a US tax advisory firm, not a law firm. Our tax strategy services focus on defensible net savings. Initial consultations and quotes are free; assessments are paid.
To discuss whether your current structure deserves a closer look, Request A Free Consult.