S Corp Requirements: What to Know When Filing as an S Corp

s corp requirements

Choosing the right business structure for your small business can often feel like a trade-off. Some entity types offer major fundraising advantages, like a C corporation, for which you can offer an unlimited number of shares, but which pay corporate taxes.

Others come with more favorable tax classification—sole proprietorships and partnerships, for instance, are only taxed once, at the owners’ personal income levels. An S corporation offers a middle path—boasting the legal advantages of a traditional corporation, alongside the tax benefits of other formats.

What is an S corporation (S corp)?

An S corporation, or S corp, is a modified form of corporation under Subchapter S of Chapter 1 of the US Internal Revenue Code, which is not subject to federal corporate tax. It is also a tax status for other business entities; for example, limited liability companies may elect to be taxed as S corps, even though their entity type is LLC. 

Like a sole proprietorship or partnership, an S corp is chiefly defined by its pass-through tax status—it passes corporate income, losses, deductions, and credits through to shareholders for purposes of federal income tax. Like C corporations (C corps), limited liability companies (LLCs), and limited liability partnerships (LLPs), S corps are legal entities distinct from ownership, meaning shareholders’ personal liability for business debt and legal damages is limited. In other words, their personal assets cannot be reached by creditors or litigants.

What are the filing requirements for an S corp?

To be an S corp, your small business must first be established as a corporation by filing articles of incorporation with the appropriate state governing authority, and pay the applicable filing fee.

Once incorporation is completed, shareholders must sign Form 2553 (Election by a Small Business Corporation), which is filed with the Internal Revenue Service (IRS). You’ll also have to appoint a board of directors, schedule annual board meetings, and write and file corporate bylaws (similar to an operating agreement for LLCs).

To qualify for S corp status, the IRS requires that a small business meet the following conditions:


An S corporation must be a domestic corporation, domiciled in the United States. It must be incorporated in one of the 50 states, Washington, DC, or one of the five inhabited US territories.

Share limits

An S corp may only issue shares to up to 100 shareholders, and shares may only be of one class of stock (common stock, which comes with voting rights but no dividend priority, as opposed to preferred stock, which comes with no voting rights but receives dividend payouts first).

Shareholder restrictions

Shareholders may only include individuals, some trusts, and estates, but cannot include partnerships, LLCs, corporations, or non-resident aliens.

Business restrictions

Some types of companies are ineligible corporations for S corp status, such as insurance companies, some financial institutions, or “domestic international sales corporations” (exporters of US goods that receive special tax treatment).

What taxes do S corps pay?

S corps are different from C corps in that they are not subject to double taxation—that is, they pass corporate income tax liability through to shareholders, which are then taxed at their personal income levels, instead of being taxed on corporate income directly by the IRS.

Still, S corps are obligated to pay certain taxes beyond corporate income tax.

Taxes S corps must pay

Your S corp small business may be liable to pay: 

  • Estimated tax: If the firm expects to owe tax of $500 or more when its income tax return is filed. Use IRS Form 1120-W if this applies to your S corp.
  • Employment tax: Social Security and Medicare taxes and federal unemployment (FUTA) tax. Use Form 941 to report your S corp’s Social Security and Medicare tax withheld from employees’ paychecks; use Form 940 to report your S corp’s FUTA tax.
  • Excise tax: These are taxes imposed on specific goods, services, and business activities—sports betting, indoor tanning services, heavy highway vehicle use, and more. Each excise tax will have its own form to file with the IRS.
  • Income tax: Not all S corps are completely exempt from paying corporate income tax. Some states and local authorities still impose tax liability on S corps. For instance, S corp businesses in California or New York City would be subject to a tax on net income. Regardless of your state tax obligations, your S corp will still have to file a Form 1120-S with the IRS to report net profits, losses, and deductions.

Taxes shareholders pay

The shareholders of your S corp small business may be liable to pay:

  • Estimated tax: S corp shareholders must make estimated tax payments if they expect to owe $1,000 or more in tax when their personal tax returns are filed. They may use Form 1040-ES to make the applicable reports to the IRS.
  • Income tax: Shareholders will be subject to federal income tax, in addition to state income tax obligations. They may use forms 1040 or 1040-SR to file income tax returns with the IRS.

What are the advantages of filing as an S corp?

There are a number of advantages to electing to file for S corporation status for your small business, mainly regarding liability protection and favorable tax treatment.

Liability protection

Shareholders in S corps enjoy limited liability protection. If the company is sued or declares bankruptcy, for example, the personal assets of shareholders are out of reach to creditors and litigants.

Avoid double taxation

S corps are pass-through entities—that is, corporate profits and losses “pass through” to shareholders, who are then taxed on that income at their personal income levels. C corps, conversely, are taxed twice: once on corporate taxable income, and again at the shareholder level. Thus, filing as an S corp may lower a company’s overall tax burden.

Tax savings for owners

S corp shareholders do not pay self-employment taxes on distributions from business profits, as they would if they were taxed as a sole proprietor, general partnership, or LLC. Owners and shareholders employed by the company are taxed on their salaries, and the company must pay that employee-shareholder reasonable compensation. Note that owners must pay themselves a “reasonable salary,” as defined by the IRS. An S corp cannot avoid employment taxes simply by paying the owner a nominal salary plus heftier dividends.

What are the disadvantages of filing as an S corp?

There are also some disadvantages to electing to file for S corporation status, including major limitations on shareholding and fundraising.

Limits on stock issuance

S corps can only issue shares to a maximum of 100 allowable shareholders, which puts a cap on fundraising goals. Stocks can only be sold to US citizens or resident aliens, and cannot go to corporate entities.

Tax implications

Corporation shareholders and/or employees who hold more than 2% of the S corp’s shares may not receive corporate health benefits as a tax-free distribution. And since taxes are paid at shareholders’ personal tax rates, high-income shareholders may pay more taxes on dividends.

Consequences for not following rules

If an S corp’s tax status is compromised, the IRS can revoke S corp status and charge back taxes for the prior three years and impose a five-year waiting period to regain S corp status. Violations that could result in revocation of S corporation status include issuing stock to a forbidden class, such as non-resident alien shareholders, or passive income exceeding 25% of gross receipts for three consecutive tax years.

Final thoughts

In many ways, S corps offer a compromise between the fundraising advantages and liability protection of a traditional C corp, and the tax-savings upside of a pass-through business entity. Though ideal for younger and leaner startups, for which every penny counts, companies with big aspirations may feel hamstrung by limits on stock issuance. Review, and possibly modify, your small business’s long-term growth plan before deciding whether an S corp is right for you.

S corp requirements FAQ

Do S corps get taxed twice?

No. Unlike C corps, which are subject to tax on both corporate income and shareholder dividends, an S corp only pays taxes via the personal income of shareholders.

How many employees does an S corp need?

While an S corp may hire employees, there is no required headcount required to maintain S corp status.

What are the disadvantages of an S corp?

Disadvantages of S corp tax classification include restrictions on stock issuance, limited fundraising capability, tax implications for shareholders, and higher scrutiny from the Internal Revenue Service (IRS).

Should I pay myself a salary from my S corp?

As an S corp owner or shareholder-employee, you must be paid a reasonable salary to maintain your S corporation status. The IRS defines a reasonable salary as at least what other businesses pay for comparable services.