One of the most powerful — and most misunderstood — features of a limited liability company is its tax flexibility. Unlike a corporation, which is locked into a specific tax structure by default, an LLC can choose from four different federal income tax regimes. That flexibility is an enormous advantage, but only if you understand your options and make a deliberate, informed choice.

This article explains each of the four ways an LLC can be taxed, when each makes sense, and — critically — exactly what you must file with the IRS to make each election.

The Four Tax Options at a Glance

Federal tax law gives LLCs remarkable flexibility. The Internal Revenue Code does not treat an LLC as a separate category — instead, it forces the LLC to be classified as one of the entity types the Code already recognizes: a sole proprietorship (called a "disregarded entity"), a partnership, an S corporation, or a C corporation. Here is a quick summary before we dive into each one.

Option 1: Disregarded Entity (Single-Member LLC Default)

If you form a single-member LLC and do nothing else, the IRS will treat it as a disregarded entity. This is the default classification for any LLC with exactly one member (owner).

"Disregarded" means the IRS ignores the LLC as a separate taxable entity. From a federal tax standpoint, it is as if the LLC does not exist. All of the LLC's income, deductions, gains, losses, and credits are reported directly on the owner's personal federal income tax return.

If the single member is an individual, the LLC's business income and expenses are typically reported on Schedule C of Form 1040, just as they would be for a sole proprietor. Net profit from Schedule C is subject to both ordinary income tax and self-employment tax (currently 15.3% on the first $176,100 of net self-employment income in 2025, and 2.9% on amounts above that threshold).

If the single member is itself a corporation or another LLC, the income flows into that entity's tax return instead.

When a Disregarded Entity Makes Sense

A disregarded entity is a good fit when:

• The business is in its startup phase with modest or unpredictable income.
• The owner wants maximum simplicity — no separate business tax return to file.
• Net profit is low enough that the self-employment tax burden is not a significant concern.
• The owner wants to use business losses to offset other personal income (losses flow directly to the 1040).
• The LLC is a rental property holding entity, where self-employment tax is generally not an issue.

Option 2: Partnership Taxation (Multi-Member LLC Default)

If an LLC has two or more members and makes no election, the IRS automatically treats it as a partnership for federal income tax purposes. Like the disregarded entity, partnership taxation is a pass-through system — the LLC itself pays no federal income tax.

Instead, the LLC files an annual informational return, Form 1065 (U.S. Return of Partnership Income). Along with Form 1065, the LLC issues a Schedule K-1 to each member, reporting that member's allocable share of the LLC's income, deductions, gains, losses, and credits. Each member then reports those K-1 figures on his or her personal tax return.

Members who are active in the business are treated as self-employed and pay self-employment tax on their distributive share of business income. Members who are passive investors generally are not subject to self-employment tax on their share of profits, but they may be subject to the 3.8% Net Investment Income Tax (NIIT) instead.

One important and often overlooked point: partnership taxation allows tremendous flexibility in allocating income and loss among members in ways that do not necessarily correspond to each member's ownership percentage, as long as the allocations have "substantial economic effect" under the Treasury regulations.

When Partnership Taxation Makes Sense

• The LLC has two or more members and income is relatively modest.
• The members want pass-through loss treatment — losses can offset other personal income.
• The members need flexible allocation of profits and losses that differs from ownership percentages.
• Simplicity of operation is a priority (no payroll required, unlike an S or C corporation).
• The business is real estate or investment-focused, where passive income rules may limit self-employment tax exposure.

Option 3: S Corporation Taxation

S corporation taxation is the most popular tax election for profitable, actively managed small businesses. It is a pass-through tax structure — like a partnership — but with a key structural difference that can produce substantial self-employment tax savings.

How It Works

When an LLC is taxed as an S corporation, the LLC files Form 1120-S (U.S. Income Tax Return for an S Corporation) each year. The LLC itself pays no federal income tax. Income and loss flow through to each member's personal return via a Schedule K-1, similar to partnership taxation.

The key difference — and the primary reason business owners choose S corporation status — is the ability to split business income into two components:

1. Reasonable salary. An owner who works in the business must pay himself or herself a "reasonable" W-2 salary. That salary is subject to payroll taxes (Social Security and Medicare) just like any employee's wages.
2. Distributions. Profits above the reasonable salary can be distributed to the owner as dividends. Those distributions are not subject to self-employment tax or payroll taxes.

For a business generating $150,000 or more in net profit, this split can easily save $10,000 to $20,000 or more per year in self-employment taxes, depending on the salary set and the net profit level. That is the reason S corporation elections are so popular.

S Corporation Eligibility Requirements

Not every LLC qualifies for S corporation status. To elect S corporation taxation, the LLC must meet all of the following IRS requirements:

• No more than 100 shareholders (members).
• All shareholders must be U.S. citizens or permanent residents. Non-resident aliens cannot be members of an S corporation.
• The LLC may have only one class of membership interest (differences in voting rights are permitted, but not differences in economic rights).
• Certain types of entities — corporations, partnerships, and most trusts — cannot be members.
• The LLC cannot be an insurance company, a financial institution that uses the bank bad debt reserve method, or a domestic international sales corporation (DISC).

When S Corporation Taxation Makes Sense

• The LLC is actively operated by its members and produces consistent net profit.
• Net profit is high enough — generally $50,000 or more above a reasonable salary — that self-employment tax savings justify the additional administrative costs (payroll, quarterly filings, Form 1120-S).
• The member(s) meet the eligibility requirements above.
• The business does not need the flexible profit/loss allocation available under partnership taxation.

Option 4: C Corporation Taxation

The fourth option is for the LLC to be taxed as a C corporation. Under C corporation taxation, the LLC is treated as a completely separate taxpaying entity. It files its own federal corporate income tax return — Form 1120 (U.S. Corporation Income Tax Return) — and pays tax on its net income at the federal corporate rate, which is currently a flat 21%.

When the LLC distributes after-tax profits to its members as dividends, those dividends are taxed again on each member's personal return — typically at qualified dividend rates (0%, 15%, or 20% depending on the member's income). This is the famous "double taxation" of C corporations. The LLC pays tax on the income once, and the member pays tax on the dividend a second time.

Why Would Any LLC Choose C Corporation Taxation?

The double-taxation disadvantage sounds terrible — and for most small, closely held businesses, it is. But C corporation taxation is not without strategic advantages in certain situations:

• Venture capital and institutional investment. Many venture capital funds are structured as pass-through entities (partnerships) whose investors are tax-exempt organizations or foreign persons. These investors generally cannot receive pass-through income from an S corporation without adverse tax consequences. A C corporation is often required to attract institutional venture funding.
• Retained earnings at a low corporate rate. If the business intends to reinvest most of its profits rather than distribute them to owners, the 21% corporate rate may be lower than the owner's marginal individual rate, creating a tax deferral benefit.
• Qualified Small Business Stock (QSBS) exclusion. Under IRC § 1202, shareholders who hold "qualified small business stock" in a C corporation for more than five years may exclude up to 100% of their gain on sale from federal income tax — a potentially enormous benefit for startup founders. LLCs taxed as partnerships or S corporations do not qualify for the QSBS exclusion.
• Employee fringe benefits. Certain fringe benefits — such as employer-paid health insurance and group term life insurance — are deductible by a C corporation but not fully deductible by an S corporation for more-than-2% shareholders.
• Anticipated public offering or acquisition. The corporate structure may simplify the legal and tax mechanics of a future IPO or sale to a public acquirer.

When C Corporation Taxation Makes Sense

• The LLC is seeking or expects to seek venture capital or institutional investment.
• The founders intend to qualify for the QSBS exclusion under IRC § 1202.
• The business will retain and reinvest the vast majority of its earnings rather than distributing them.
• The LLC plans to go public or be acquired by a publicly traded company.

For the typical small business — a service-based business, a local retail operation, a professional practice — C corporation taxation is rarely the right choice because of double taxation. But for high-growth startups with investor ambitions, it can be exactly right.

Side-by-Side Comparison

The table below summarizes the key differences among the four tax classifications.

A Word About Arizona State Taxes

This article focuses on federal income tax. Arizona generally conforms to the federal tax classification of an LLC for Arizona income tax purposes. If your LLC is taxed as a disregarded entity or partnership at the federal level, it will be treated similarly for Arizona income tax. If your LLC elects S or C corporation status federally, Arizona will follow that classification.

Arizona does impose a Transaction Privilege Tax (TPT) — often called a sales tax — on certain business activities. The LLC's federal tax classification does not affect its TPT obligations. Arizona also has its own corporate income tax rate for C corporations (currently 4.9%) that applies in addition to the federal corporate rate.

State tax implications are an important part of any tax planning discussion. Be sure to address both federal and Arizona state taxes with your CPA or tax attorney.

Frequently Asked Questions

The Bottom Line

The LLC is a uniquely flexible business structure, and its tax flexibility is one of its greatest advantages. The four tax options — disregarded entity, partnership, S corporation, and C corporation — each serve a different type of business owner at a different stage of business growth.

Most small business owners benefit most from the S corporation election once their business reaches consistent profitability above a reasonable salary. The savings in self-employment taxes can fund a vacation, a retirement contribution, or a marketing campaign. But the right answer depends entirely on your specific facts: your income level, your number of members, the nature of your business, and your plans for the future.

Do not leave this decision to chance or default. Make a deliberate, informed choice — and make it with professional guidance.