What Is an S Corp? Definition, Eligibility, and How to Elect It

What Is an S Corporation?

The business itself is still legally a corporation or LLC. S corp status only changes how it’s taxed at the federal level. You’ll need to form your corporation or LLC at the state level first, then make the election with the IRS. The IRS maintains a dedicated S corporations resource page covering eligibility, filing requirements, and related forms.

How S Corp Taxation Works

The S corp files Form 1120-S, an informational tax return, with the IRS each year. The company pays no federal income tax on that return. Instead, each shareholder receives a Schedule K-1 showing their individual share of the business’s income, deductions, and credits. Shareholders report those K-1 figures on their personal Form 1040 and pay tax at their individual rate.

The reasonable salary requirement is where the tax math gets more specific. If you actively work in the business, the IRS requires you to pay yourself a market-rate salary, meaning compensation comparable to what you’d pay someone else to do your job. That salary is subject to payroll taxes (Social Security and Medicare), just like any employee’s wages.

Distributions above that salary are generally not subject to self-employment tax. If your S corp earns $100,000 and you pay yourself a $60,000 salary, only the $60,000 is subject to payroll taxes. The remaining $40,000 distribution typically is not, which can produce meaningful savings compared to a default LLC, where self-employment tax applies to all net profits.

Who Qualifies for S Corp Status? Eligibility Requirements

The IRS sets specific criteria under IRC §1361, and you must meet every single one. Miss one, and the IRS rejects the election outright.

S Corp Eligibility Checklist

• Domestic entity only. Your corporation must be formed under the laws of a U.S. state, Washington D.C., or a U.S. territory. Foreign entities don’t qualify.
• No more than 100 shareholders. Certain family members may count as a single shareholder, so a large family-owned business may have more individuals involved than the number suggests.
• All shareholders must be U.S. citizens or permanent residents. This rule applies to every shareholder, not just a majority.
• Shareholders must be individuals, certain trusts, or estates. Partnerships, corporations, and most multi-member LLCs cannot hold S corp stock.
• Only one class of stock. Differences in voting rights are allowed, but not differences in distribution or liquidation rights.
• Not an ineligible corporation type. Certain financial institutions, insurance companies, and domestic international sales corporations are excluded.
• Must use a calendar tax year unless the IRS approves a fiscal year exception.

If you’re an LLC owner, you can elect S corp tax treatment without converting to a corporation first. The IRS applies these shareholder rules to LLC members for purposes of the election.

Who Cannot Be an S Corp Shareholder?

Nonresident aliens disqualify the election entirely. Even a 1% interest held by a nonresident alien voids the election.

Corporations and partnerships cannot hold S corp stock. This matters if a personal holding company or investment partnership wants to take a stake in the S corp, because that structure won’t work.

Most trusts are ineligible, but some are not. Qualified Subchapter S Trusts (QSSTs) and Electing Small Business Trusts (ESBTs) can hold stock under strict compliance requirements. Grantor trusts, where the grantor is a U.S. individual treated as the owner for income tax purposes, can also temporarily hold S corp stock.

Eligibility isn’t a one-time check. If a shareholder inadvertently transfers their interest to an ineligible party, or dies and their interest passes to a trust that hasn’t made the proper election, the S corp election terminates.

How to Elect S Corp Status: Step-by-Step

1. Form your corporation or LLC at the state level. File your articles of incorporation or organization with your state and obtain your Employer Identification Number (EIN) from the IRS before you do anything else.
2. Confirm you meet every IRS eligibility requirement. Every condition must be satisfied: shareholder count, citizenship, stock class, and entity type. One disqualifying factor voids the election entirely.
3. Complete IRS Form 2553. You’ll need your business name, EIN, date of incorporation, state of incorporation, fiscal year end, and the proposed effective date. Fill out every field, as incomplete forms are a leading reason the IRS returns elections unprocessed.
4. Collect a signature from every shareholder. The IRS rejects any form that isn’t signed by all shareholders.
5. File Form 2553 with the correct IRS service center. Mail or fax to the address or fax number specified in the Form 2553 instructions for your state. If you mail it, send via certified mail and keep the receipt. If you fax it, keep a confirmation page.
6. Wait for your CP261 confirmation notice from the IRS. Processing typically takes up to 60 days. If you haven’t received the notice after that window, contact the IRS Business and Specialty Tax Line. Keep the CP261 permanently, as it’s your official proof of S corp tax status.

Form 2553 Deadlines

• Existing corporations or LLCs: File no later than March 15 of the tax year in which you want the election to take effect (for calendar-year entities).
• Newly formed entities: File within 75 days of the date of formation or the start of the tax year, whichever is earlier.
• If you miss the deadline: The election automatically shifts to the following tax year.

What to Do if You Miss the S Corp Election Deadline

The IRS offers late election relief under Revenue Procedure 2013-30 for entities that missed the deadline due to reasonable cause. To qualify, your business must have operated as if it were an S corp during the period in question and must submit Form 2553 with a written statement explaining the reasonable cause. The relief process has its own specific requirements, so work with a tax professional before filing late.

Ongoing Compliance Requirements After Electing S Corp Status

Annual tax filing: Form 1120-S. Every S corp must file Form 1120-S with the IRS each year, even if the business had no income, by March 15 for calendar-year entities. Extensions are available using Form 7004.

Schedule K-1 for every shareholder. The S corp must prepare and distribute a Schedule K-1 to each shareholder by the same deadline, reporting each shareholder’s proportionate share of income, deductions, credits, and other tax items.

Payroll compliance for owner-employees. If you work in the business, you must run payroll, withhold and remit payroll taxes, and file quarterly payroll returns (Form 941) and annual wage reports (Form W-2 and Form W-3). Many S corp owners work with a payroll service provider to manage this.

State-level filings. Depending on your state, you may need to file a separate state income tax return, pay a franchise tax, or submit annual reports. Some states, including California, New York, and New Jersey, impose their own S corp-level taxes or require a separate state S corp election. Check your state’s requirements every year.

Corporate formalities (for S corps structured as corporations). If your S corp is legally a corporation rather than an LLC taxed as an S corp, you’re expected to hold annual shareholder and director meetings, maintain minutes, keep corporate records, and avoid commingling personal and business funds. Skipping these formalities can expose shareholders to personal liability.

S Corp vs. C Corp: Key Differences

A C corporation pays federal income tax on its profits at the entity level. When it distributes those profits to shareholders as dividends, shareholders pay tax again. That’s the double taxation pass-through treatment eliminates.

That said, businesses pursuing venture capital, planning an IPO, or bringing on foreign investors often need the flexibility only a C corp allows: multiple stock classes, unlimited shareholders, and no citizenship restrictions. If your growth strategy involves outside equity financing or a future public offering, S corp restrictions would work against you.

S Corp vs. LLC: Which Is Better for a Small Business?

An LLC is a legal entity structure; an S corp is a tax election. They’re not opposites — they’re different layers of the same decision. An LLC can elect to be taxed as an S corp while remaining an LLC legally.

A default LLC keeps things simple and low-cost, the right fit when profits are modest or inconsistent. Once your net income reaches a level where self-employment tax savings outweigh payroll administration costs, the S corp election starts making real financial sense. For most owners, the LLC-taxed-as-S-corp path hits that balance best: you keep the simpler LLC structure while capturing the payroll tax advantage.

Pros and Cons of an S Corp

Advantages of an S Corp

• No entity-level federal income tax. Profits pass through directly to shareholders’ personal returns.
• Self-employment tax savings on distributions. Only your reasonable salary is subject to payroll taxes. Distributions above that salary generally aren’t.
• Personal liability protection. Shareholders are generally not personally responsible for business debts or legal judgments.
• Losses pass through, too. If the business runs at a loss, shareholders can potentially use that loss to offset other income on their personal returns, subject to IRS basis and at-risk rules.
• Corporate credibility without C corp taxation. An S corp carries the structure and formality of a corporation, useful for contracts, financing, and business relationships, without the corporate-level tax bill.

Disadvantages of an S Corp

• Strict ownership rules. The 100-shareholder cap, citizenship requirements, and restrictions on who can hold stock limit flexibility as the business grows.
• Reasonable salary requirement. Working owners must pay themselves market-rate compensation, which means mandatory payroll filings and associated costs.
• One class of stock only. You can’t offer investors preferred shares or different economic rights.
• State-level complications. Some states don’t recognize S corp status or impose their own franchise taxes, so federal election alone doesn’t guarantee state tax savings.
• Ongoing compliance costs. Form 1120-S, Schedule K-1s, and payroll filings add administrative overhead and professional fees that a default LLC doesn’t require.

When an S Corp Makes Sense, and When It Doesn’t

When the S corp election makes sense.

• Your net income is consistently above $40,000–$50,000 per year. The self-employment tax savings on distributions above your reasonable salary can meaningfully exceed the cost of payroll administration and Form 1120-S filing. The higher your net income above that threshold, the stronger the case.
• You actively work in the business. The SE tax savings only apply if you’re drawing a salary and taking distributions. Passive owners gain much less from S corp treatment.
• You want liability protection and corporate credibility without triggering double taxation at the entity level.

When the S corp election likely doesn’t make sense.

• Your profits are low or inconsistent. If net income falls below $40,000, mandatory payroll costs and compliance fees may wipe out any tax savings.
• You plan to raise venture capital or bring on foreign investors. S corp restrictions on shareholder eligibility and stock classes make outside equity financing structurally difficult.
• Your business is in its early years. Start-up losses and unpredictable cash flow make the payroll compliance burden hard to justify.

The LLC-to-S corp path is simpler than most owners expect. An existing LLC does not need to convert to a corporation to get S corp tax treatment. It can file Form 2553 directly.

Check your state’s rules before you file. Some states, including California, New York, and New Jersey, require a separate state-level S corp election or impose their own franchise tax. Federal approval alone doesn’t guarantee state tax savings.

Common S Corp Election Mistakes to Avoid

• Missing the filing deadline. For a calendar-year entity, Form 2553 must reach the IRS by March 15. New entities get a 75-day window from formation. File after either deadline and your election shifts to the following tax year.
• Skipping a shareholder signature. One missing signature and the IRS returns the form unprocessed.
• Adding an ineligible shareholder post-election. Bringing on a nonresident alien, a corporation, or a partnership after your election is approved terminates your S corp status entirely, often with immediate tax consequences.
• Accidentally issuing a second class of stock. A loan structured with equity-like terms or side agreements giving certain shareholders preferential distributions can be treated by the IRS as a second stock class, voiding the election.
• Paying yourself little or no salary. Taking distributions while drawing minimal compensation is one of the IRS’s primary audit triggers for S corp owners.
• Ignoring state-level requirements. Several states require a separate state-level S corp election, and others impose their own franchise taxes regardless of what the IRS has approved.

How to Start Your S Corp With Inc Authority

Inc Authority has helped more than 4 million businesses get started over more than 25 years, including thousands of small business owners who have used our platform to form their corporation or LLC and file for S corp tax status. Whether you’re starting from scratch or converting an existing LLC, Inc Authority can help you form your entity, prepare and file Form 2553, and stay on top of ongoing compliance requirements.

Ready to take the next step? Inc Authority’s business formation services walk you through the process from entity formation to S corp election, with support available to answer your questions along the way.

Frequently Asked Questions About S Corps

What Is an S Corp in Simple Terms?

An S corp is a tax status, not a business entity type, that lets a corporation’s or LLC’s profits and losses pass directly through to the owners’ personal tax returns. The business itself pays no federal income tax. Each owner reports their share of income on their individual return and pays tax at their personal rate.

Is My LLC an S Corp or a C Corp?

An LLC is neither by default. A single-member LLC is taxed as a sole proprietorship; a multi-member LLC is taxed as a partnership. If your LLC filed Form 2553, it’s taxed as an S corp. If it filed Form 8832 but not Form 2553, it’s taxed as a C corp.

What Is Pass-Through Taxation and How Does It Work for an S Corp?

Pass-through taxation means the business itself pays no federal income tax. Profits and losses flow to each shareholder’s personal return via a Schedule K-1, and each shareholder pays tax at their individual rate. The S corp still files Form 1120-S annually as an informational return, but no tax is owed at the entity level.

What Are the IRS Eligibility Requirements for S Corp Status?

Your business must be a domestic entity with no more than 100 shareholders, all of whom must be U.S. citizens or permanent residents. Shareholders must be individuals, certain trusts, or estates, not corporations or partnerships. The entity can have only one class of stock and cannot be a disqualified entity type such as certain financial institutions or insurance companies.

How Many Shareholders Can an S Corp Have?

No more than 100. Certain family members, including a spouse, ancestors, and lineal descendants, may be counted as a single shareholder for purposes of this limit.

Who Cannot Be a Shareholder in an S Corp?

Nonresident aliens, corporations, partnerships, and most multi-member LLCs cannot hold S corp stock. Even a single ineligible shareholder voids the election. Certain trusts, including QSSTs, ESBTs, and grantor trusts, are permitted under specific conditions.

What Is IRS Form 2553 and How Do You File It?

Form 2553 is the IRS form you use to elect S corp tax status. Complete it with your business name, EIN, incorporation date, state of incorporation, and proposed effective date, then collect signatures from every shareholder. File by mail or fax to the IRS service center designated for your state in the form instructions. Keep proof of submission until you receive the CP261 confirmation notice.

What Is the Deadline to Elect S Corp Status?

For existing calendar-year entities, you must file Form 2553 by March 15 of the tax year you want the election to apply. Newly formed entities have 75 days from the date of formation. Missing either deadline pushes the election to the following tax year.

What Happens if You Miss the S Corp Election Deadline?

The election defaults to the following tax year. However, the IRS offers late election relief under Revenue Procedure 2013-30 if your business can show reasonable cause and demonstrate it operated as an S corp during the relevant period. A tax professional should handle any late-election filing.

Can an LLC Elect S Corp Status?

Yes. Your LLC can file Form 2553 directly to be taxed as an S corp without converting to a corporation. The LLC remains an LLC legally; only its federal tax treatment changes. All standard S corp eligibility requirements apply to the LLC’s members.

What Is the “Reasonable Salary” Requirement for S Corp Owners?

If you work in the business, you must pay yourself a salary comparable to what the market would pay someone else to perform the same role. That salary is subject to payroll taxes. The IRS closely watches S corps where owner-employees take little or no salary, as it’s one of the agency’s primary audit triggers for this entity type.

What Are the Ongoing Compliance Requirements After Electing S Corp Status?

S corps must file Form 1120-S and distribute Schedule K-1s to all shareholders annually by March 15. Owner-employees must run payroll and file quarterly Form 941 returns and annual W-2s. Some states require separate state filings or impose their own S corp taxes. Corporations (as opposed to LLCs taxed as S corps) must also maintain corporate formalities such as meeting minutes and separate financial records.

What Are the Most Common Reasons an S Corp Election Gets Rejected?

The most common reasons are a missing shareholder signature on Form 2553, filing after the applicable deadline, and failing to meet an eligibility requirement at the time of filing, such as having an ineligible shareholder or more than one class of stock. Incomplete forms are also frequently returned unprocessed.

How Do You Lose S Corp Status After It’s Been Granted?

S corp status terminates automatically if your business violates any eligibility requirement, for example by exceeding 100 shareholders, adding an ineligible shareholder, or inadvertently creating a second class of stock. The business then reverts to C corp taxation, which can trigger significant tax consequences. Reinstatement requires a new Form 2553 and, in some cases, a five-year waiting period. Shareholders can also voluntarily revoke the election by filing a statement signed by holders of more than 50% of outstanding stock.

Do States Have Their Own S Corp Election Requirements?

Yes, in many cases. The federal Form 2553 election does not automatically apply at the state level everywhere. New York and New Jersey require a separate state S corp election. California recognizes the federal election but imposes a 1.5% franchise tax on S corp net income, with an $800 annual minimum. A handful of states do not recognize S corp status at all. Verify your state’s rules before assuming federal approval covers your state tax treatment.

Can an S Corp Have Employees Who Are Not Shareholders?

Yes. The 100-shareholder limit applies only to equity owners. An S corp can employ any number of non-shareholder staff, who receive standard W-2 wages, pay ordinary payroll taxes, and do not receive Schedule K-1s.

How Long Does It Take for the IRS to Approve an S Corp Election?

The IRS typically issues a CP261 confirmation notice within 60 days of receiving Form 2553. If you haven’t received it after 60 days, contact the IRS Business and Specialty Tax Line.

What Taxes Does an S Corp Pay?

An S corp pays no federal income tax at the entity level. It is responsible for payroll taxes on wages paid to owner-employees and other staff and must file Form 1120-S annually. Some states impose a separate franchise tax or minimum annual tax on S corps regardless of profitability.