LLC vs S-Corp Tax Differences: Which Structure Saves More?

The Tax Gap That Changes Everything

A self-employed consultant earning $150,000 net profit as a single-member LLC owes $21,195 in self-employment (SE) tax alone—15.3% on the first $160,200 of net earnings as of 2024. That same owner, operating as an S-Corp paying herself a $70,000 salary and taking $80,000 as a distribution, cuts SE tax to roughly $10,706. The structure difference, not the income, creates the savings. Understanding why requires unpacking how the IRS treats each entity type.

How LLCs Are Taxed by Default

The IRS does not recognize the LLC as a tax entity. A single-member LLC is taxed as a sole proprietorship by default; a multi-member LLC is taxed as a partnership. In both cases, all net business income flows directly to the owner's Schedule C or Schedule E and is subject to self-employment tax of 15.3% (up to the Social Security wage base of $160,200 for 2024, then 2.9% Medicare on everything above).

Simple and invisible. No payroll, no corporate filings, no separate tax return—just Schedule C attached to Form 1040.

• Single-member LLC files Schedule C; all net profit = SE income
• Multi-member LLC files Form 1065; each partner's share = SE income
• No distinction between "salary" and "profit" for SE tax purposes
• QBI deduction (Section 199A) can reduce income tax but not SE tax

How S-Corps Split Income and Why It Matters

An S-Corp is a pass-through entity—profits flow to shareholders and are taxed at personal rates, avoiding corporate income tax. The critical difference: S-Corp owners who work in the business must pay themselves a "reasonable salary," which is subject to payroll taxes (FICA). Distributions above that salary are not subject to FICA or SE tax.

This split is the engine of S-Corp tax savings. By pushing income above a reasonable salary into distributions, owners legally reduce the amount subject to payroll taxes.

The Reasonable Salary Requirement

The IRS mandates that S-Corp owner-employees receive compensation "reasonable" for the services they perform. There is no bright-line rule, but the IRS scrutinizes returns where salaries are suspiciously low. Courts and audits reference factors including what comparable employees earn, hours worked, and business profitability.

Setting salary too low is the most common S-Corp audit trigger.

• BLS wage data and industry surveys are common benchmarks
• An owner paying herself $20,000 on $500,000 of net profit invites scrutiny
• Salary must cover at least the Social Security wage base in high-income cases to avoid obvious manipulation
• S-Corps with losses have no obligation to pay salary (no SE tax issue exists)

Break-Even Point: When S-Corp Saves Enough to Justify Costs

S-Corps come with real overhead: payroll administration, Form 1120-S filing (often $800–$2,000 via a CPA), state-level fees, and potential franchise taxes. The SE tax savings must exceed these costs.

Most tax professionals cite $40,000–$60,000 in net profit as the minimum threshold where S-Corp election begins producing net savings after overhead. Below that, the LLC's simplicity wins on cost.

State-Level Complications

Several states impose additional S-Corp taxes that erode savings. California charges a minimum franchise tax of $800 per year plus a 1.5% S-Corp tax on net income. New York City does not recognize S-Corp status, taxing the entity as a C-Corp for city purposes. Illinois, Massachusetts, and Tennessee have their own quirks. Federal savings calculations must be adjusted for state exposure before comparing structures.

Retirement Contributions and Other Deductions

Both structures allow significant retirement deductions, but the mechanics differ. An LLC owner contributes to a SEP-IRA or Solo 401(k) based on net self-employment income. An S-Corp owner's retirement contributions are based on W-2 wages, which can limit or affect contribution ceilings. High earners often find that Solo 401(k) contribution limits remain comparable across both structures when salary is set appropriately.

The Conversion Path

An existing LLC can elect S-Corp tax treatment by filing IRS Form 2553. The LLC retains its legal structure—the election only changes how it is taxed. This election must generally be made by March 15 of the tax year it is to take effect (or within 75 days of formation). Late elections are possible but require IRS approval. An LLC with S-Corp election is often referred to as an "LLC taxed as an S-Corp" — it is not a separate legal entity type.

This article is for informational purposes only and does not constitute financial or tax advice.