Your business’s entity type is the legal classification it takes on at formation, and it controls two things owners care about most: whether your personal assets are exposed if the business is sued or can’t pay its debts, and how the IRS taxes what the business earns. Every formal business in the United States falls into one of a handful of categories, sole proprietorship, general partnership, limited partnership, LLC, C corporation, or nonprofit, and the choice follows the business through every tax return, contract, and lawsuit it encounters.
Why the Classification Matters
The law treats certain entity types as separate legal persons. An LLC or corporation can sign contracts, own property, and be sued independently of the people behind it. That separation is the foundation of liability protection: if the business loses a lawsuit or can’t pay a debt, creditors generally can’t reach the owner’s personal bank accounts or home. Entity types without that separation, sole proprietorships and general partnerships, offer no such shield.
Tax treatment is the other consequence. Your classification decides which forms you file and whether the business itself pays income tax or passes profits through to owners’ personal returns. A C corporation files Form 1120 and pays tax at the entity level.1Internal Revenue Service. About Form 1120, U.S. Corporation Income Tax Return A sole proprietor reports everything on Form 1040. That difference drives real dollars each April.
Sole Proprietorship
This is the default. If you start freelancing, selling goods, or offering services without filing any formation paperwork with a state, you’re a sole proprietor. The law treats you and the business as the same person. Every dollar the business earns is your personal income, and every debt the business owes is your personal obligation.
You report business income and expenses on Schedule C of your Form 1040.2Internal Revenue Service. About Schedule C (Form 1040), Profit or Loss from Business (Sole Proprietorship) If your net earnings exceed $400, you also owe self-employment tax, calculated on Schedule SE, which covers Social Security and Medicare.3Internal Revenue Service. Instructions for Schedule SE (Form 1040) There’s no corporate veil. If a customer sues and wins, they can reach your personal savings and property.
General Partnership
A general partnership forms automatically when two or more people go into business together to share profits. No state filing is required. The business files an annual information return on Form 1065, and each partner reports their share on their personal return.4Internal Revenue Service. Partnerships Like a sole proprietorship, the partnership itself pays no income tax.
Liability is where general partnerships get dangerous. Every partner is personally responsible for the partnership’s debts and legal judgments, including obligations created by the other partners’ business decisions. If your partner signs a bad contract, you’re on the hook too.
Limited Partnership
A limited partnership (LP) splits its owners into two groups. General partners run the business and carry unlimited personal liability. Limited partners invest money, stay out of management, and risk only what they put in. LPs are pass-through entities filing Form 1065, and unlike general partnerships they require a formal state filing to create, because the limited partners’ protection depends on state recognition of the structure.4Internal Revenue Service. Partnerships LPs show up most often in real estate investment, family wealth planning, and venture capital.
Limited Liability Company
The LLC is the most popular entity type for new small businesses. It puts a legal barrier between the business and its owners (called members), shielding personal assets from business debts and lawsuits, and the IRS gives it flexible tax treatment rather than locking it into one category.
A single-member LLC is treated by default as a “disregarded entity,” meaning the IRS ignores it for income tax and the owner reports everything on their personal return, the same as a sole proprietor. An LLC with two or more members defaults to partnership taxation.5Internal Revenue Service. Single Member Limited Liability Companies Either type can file Form 8832 to elect corporate tax treatment instead, which also opens the door to an S corporation election.6Internal Revenue Service. Limited Liability Company – Possible Repercussions
The liability protection isn’t automatic or bulletproof. Members need to keep business finances completely separate from personal accounts, maintain adequate records, and actually operate the LLC as a distinct entity. When owners treat the business like a personal piggy bank, courts can pierce the veil and hold them personally liable. A written operating agreement defining each member’s ownership stake, voting rights, profit distribution, and exit procedure is the backbone of a well-run LLC.
Every state also requires LLCs and corporations to designate a registered agent, a person or service with a physical in-state address who accepts lawsuits and government notices on the business’s behalf. Without one, the state can revoke the business’s good standing.
C Corporation
A C corporation is a fully independent legal entity, separate from the people who own its shares. Forming one means filing articles of incorporation with the state, adopting bylaws, appointing a board of directors and officers, and issuing stock. The formalities are part of the deal. Skip them, and a court may treat the corporation as a shell and hold shareholders personally responsible. Most states require at least one board meeting and one shareholder meeting per year, with minutes recorded and corporate records maintained.
The defining tax feature of a C corporation is double taxation. The corporation pays federal income tax on its profits at a flat 21 percent rate.7Office of the Law Revision Counsel. 26 U.S. Code 11 – Tax Imposed When those after-tax profits are distributed to shareholders as dividends, the shareholders pay personal income tax on the dividends. The same money is taxed twice.
That sounds punishing, but C corporations offer things the other structures can’t: unlimited shareholders, multiple classes of stock, and the ability to attract institutional investors. If you’re planning to raise venture capital or go public, this is typically the required structure.
S Corporation Election
An S corporation isn’t a separate entity you create at the state level. It’s a federal tax election that an existing LLC or corporation makes by filing Form 2553 with the IRS.8Internal Revenue Service. S Corporations The election avoids double taxation by passing income through to shareholders’ personal returns, while keeping the liability protection of the underlying entity.
Not every business qualifies. Under Subchapter S of the Internal Revenue Code, the company must be a domestic business, have no more than 100 shareholders (all of whom must be individuals, certain trusts, or estates), issue only one class of stock, and not fall within the ineligible categories such as certain financial institutions and insurance companies.9Office of the Law Revision Counsel. 26 U.S. Code 1361 – S Corporation Defined Violate any of these after the election, and the IRS can revoke S status.
The biggest practical benefit is reducing self-employment tax. Instead of paying 15.3 percent on all business profits, an S corp owner-employee takes a salary (subject to payroll tax) and receives remaining profits as distributions (not subject to self-employment tax). The IRS requires that the salary be “reasonable compensation” for the work the owner actually performs.10Internal Revenue Service. S Corporation Compensation and Medical Insurance Issues Setting a salary artificially low to dodge payroll tax is one of the fastest ways to invite an audit, and the IRS can reclassify distributions as wages retroactively.
Nonprofit
A nonprofit is organized to pursue a charitable, educational, religious, scientific, or similar mission rather than generate profit for owners. Most nonprofits incorporate at the state level like any other corporation, but the governing documents must prohibit distributing profits to individuals. Once the state entity exists, the organization can apply to the IRS for tax-exempt status under Section 501(c)(3).11Internal Revenue Service. Exemption Requirements – 501(c)(3) Organizations
Tax-exempt status comes with annual filing obligations. Most nonprofits must file some version of Form 990 each year, and an organization that fails to file for three consecutive years automatically loses its tax-exempt status.12Internal Revenue Service. Automatic Revocation of Exemption Reinstatement requires a new application and, in many cases, back taxes on any revenue earned during the gap.
Professional Entities
Doctors, lawyers, accountants, architects, and other licensed professionals often can’t form a standard LLC or corporation. Many states require them to use a Professional Limited Liability Company (PLLC) or a Professional Corporation (PC). These structures work like their regular counterparts in most respects, with one critical limit: a PLLC or PC protects you from a business partner’s malpractice claims and from the entity’s general business debts, but it does not protect you from liability for your own professional negligence. If you personally commit malpractice, the structure won’t shield your personal assets. Rules on which professions must use professional entities vary by state, so check your state’s licensing requirements before choosing.
How Entity Type Affects Self-Employment Tax
Beyond income tax, entity type determines whether you pay self-employment tax, and this is where the real money shows up for many small-business owners. Sole proprietors and general partners pay a combined 15.3 percent self-employment tax on net earnings, covering both the employer and employee portions of Social Security (12.4 percent) and Medicare (2.9 percent).13Social Security Administration. Contribution and Benefit Base The Social Security portion applies to earnings up to $184,500 in 2026; the Medicare portion has no cap.14Social Security Administration. 2026 Cost-of-Living Adjustment (COLA) Fact Sheet
That 15.3 percent hits on top of regular income tax, which is why the S corp election appeals to profitable small businesses. An S corp owner earning $150,000 in business profit might pay herself a $90,000 salary (subject to payroll tax) and take the remaining $60,000 as a distribution (not subject to payroll tax). The payroll tax savings on that $60,000 would be roughly $9,180. C corporation owners who work in the business pay the employee half of payroll tax on their salary while the corporation pays the employer half, so the economic result on salary is similar. The distinction is that C corp profits distributed as dividends face double taxation rather than self-employment tax.
Formation and Ongoing Costs
Every entity type beyond a sole proprietorship requires a state filing to create, and those filings carry fees. LLC formation fees range from roughly $35 to $500 depending on the state, with most falling between $50 and $200. Corporation filing fees land in a similar band. Some states also charge franchise taxes or require costly publication of the formation notice in local newspapers.
The upfront fee is just the start. Most states require LLCs and corporations to file an annual or biennial report, with fees ranging from $0 in a handful of states to over $800 where a franchise tax is bundled in. Miss the filing and the state can administratively dissolve the entity, which strips away your liability protection until you reinstate. A registered agent is another ongoing cost if you use a commercial service rather than serving as your own. Factor the recurring obligations in before you choose. The cheapest structure to form isn’t always the cheapest to maintain.