Choosing the right legal entity is one of the most important decisions for any start‑up. The entity type you select affects taxation, liability, and flexibility in operations. Two common options for businesses with multiple owners are multimember LLCs and S corporations. Both provide liability protection and pass‑through taxation, but they differ in key ways.
Multimember LLCs
A multimember LLC blends corporate liability protection with partnership tax benefits. Members are shielded from personal liability, and all can participate in management without losing that protection.
Tax items — income, losses, deductions, and credits — pass through to members’ personal returns. However, members typically owe self‑employment tax on their share of income. In 2026, this includes Social Security tax (12.4% on the first $184,500 of income) and Medicare tax (2.9% on all income). Half of this self‑employment tax is deductible.
It’s important to note that some professional practices may be restricted from forming LLCs under state laws or professional standards.
S Corporations
An S corporation is a tax designation for qualifying domestic corporations. Like LLCs, it shields shareholders from personal liability and passes income through to owners’ personal returns.
The main advantage: shareholder‑employees don’t pay self‑employment tax on their share of profits, as long as they receive “reasonable” compensation subject to payroll taxes.
However, S corporations face stricter rules. They must comply with eligibility requirements, limit the number and type of shareholders, and maintain simple capital structures.
Key Differences Between LLCs and S Corporations
- Loss Deductions: LLC members can increase tax basis through entity‑level liabilities, while S corporation shareholders only gain basis from personal loans to the corporation.
- Asset Transfers: LLCs allow more flexibility in tax‑free transfers of assets between members and the entity.
- Basis Step‑Up: When an LLC interest is purchased, the new member’s share of assets can be stepped up, reducing future tax liability.
- Allocations: LLCs can allocate income and losses disproportionately among members. S corporations must allocate strictly based on ownership percentages.
Make a Tax‑Smart Choice
Both structures offer benefits, but the right choice depends on your business goals, industry, and tax situation. Careful planning is essential to maximize advantages and avoid pitfalls. Consult with tax and legal advisors before making your decision to ensure the best fit for your start‑up.