Knowledge Center | Business formation
Every business structure, explained without a sales pitch at the end.
Sixteen structures and designations, what each one actually is, and what you should understand before anyone recommends one to you.
The three groups: legal structures, tax classifications, and registrations that aren't entities at all.
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These aren't sixteen options on one menu
Most comparison articles list all of these side by side as though you walk in and pick one, like a sandwich. That's misleading, because the items belong to three different categories doing three different jobs.
- What you form with your state.
- Determines legal existence and liability separation.
- Sole proprietorship, partnerships, LLC, corporation, and the professional and special-purpose variants.
- How the IRS treats whatever you formed.
- Some are defaults, some are elections.
- Disregarded entity, partnership, C corporation, S corporation.
- Not entities at all, though they're often discussed as if they were.
- DBA, single versus multi-member, anonymous LLC, non-reporting LLC.
- Confusing these with structures causes real mistakes.
The clearest way to hold it: you choose a structure with your state, a tax treatment with the IRS, and you may add registrations on top. Three decisions, not one. The full breakdown of the first two ->
Group one
Legal business structures
What you form with a state. Availability varies, and several of these don't exist or are restricted in particular states.
| Structure | What it is | What to understand |
|---|---|---|
| Sole proprietorship | An individual running a business without forming a separate entity. | Simple to start. No separation at all between personal and business liability. It's the default if you start trading without forming anything. |
| General partnership | Two or more people conducting business together for profit. | Can form without anyone intending it, which is the problem. Partners generally carry personal liability for the business's obligations - including the ones their partner created while they weren't looking. |
| Limited partnership (LP) | A partnership with general and limited partners. | General partners manage and generally bear personal liability. Limited partners generally get protection but give up management involvement to keep it. |
| Limited liability partnership (LLP) | A registered partnership providing liability protection to its partners. | Common among professional firms. Availability and the scope of protection vary by state, and several states restrict it to listed professions. |
| Limited liability company (LLC) | A separate legal entity owned by members. | Flexible on management and on tax treatment. Liability protection with important exceptions that depend on maintaining real separation. |
| Corporation | A separate legal entity owned by shareholders. | Formal governance: bylaws, directors, officers, meetings, minutes. Can issue stock, which matters if you'll raise outside investment. |
| Professional LLC (PLLC) | A specialized LLC for licensed professionals, in states that offer it. | State licensing rules apply. Not available everywhere and not for every profession. |
| Professional corporation (PC) | A corporation organized to deliver regulated professional services. | Used where state law requires or permits licensed professionals to incorporate this way. |
| Benefit corporation | A for-profit corporation with legally recognized public-benefit obligations. | Pursues return alongside stated public benefits. Not a nonprofit, and not a tax status. |
| Nonprofit corporation | Organized for qualifying purposes rather than distributing profit to owners. | Federal tax exemption is not automatic. It requires separate recognition from the IRS, which is its own application with its own requirements. |
| Cooperative | Owned or democratically controlled by its participating members. | Members take part in governance and share benefits under the cooperative's own rules. |
We form these for a living, which is why the list is honest
Most comparison articles are written by companies that make money on one specific answer, and it shows in which option gets the glowing paragraph. We file entities in several states and make the same fee whichever one you pick, so there's nothing in it for us to steer you.
Group two
Federal tax classifications
How the IRS treats what you formed. This is a separate decision from the structure, made with a different agency.
| Classification | What it means |
|---|---|
| Disregarded entity | Default for a single-member LLC. The IRS largely ignores the entity and treats the activity as the owner's. |
| Partnership | Default for a multi-member LLC and for partnerships. Files an informational return; income passes through to members. |
| C corporation | Default for a corporation, electable by an LLC. The entity pays its own federal income tax, and distributed profit can be taxed again at the shareholder level. |
| S corporation | An election, not an entity type. Income generally passes through to qualifying shareholders, with eligibility limits and reasonable-compensation rules attached. |
The S corp question is the one most people arrive with, and it has a real answer that depends on your numbers. The mechanism, and where the crossover point comes from ->
Group three
Things that sound like structures and aren't
Every item here gets discussed as though it were an entity type. None of them are, and the confusion is expensive.
| Term | What it actually is | The misunderstanding |
|---|---|---|
| DBA / fictitious name | A registered trading name. | People believe it creates liability protection. It creates precisely none. It is a nickname with paperwork. An existing LLC can trade under a DBA without forming anything new. |
| Single-member LLC | An LLC with one owner. | Not a separate state-law entity type. The member count sets the default federal tax treatment, not the legal form. |
| Multi-member LLC | An LLC with more than one owner. | Same entity type as above. Adding a member generally changes the default tax classification to partnership, bringing a new filing obligation. |
| Anonymous LLC | An ordinary LLC formed where owner names aren't required on public records. | Public privacy, not legal anonymity. Banks, tax authorities, and courts can still identify you. Full guide. |
| Non-reporting LLC | A label describing an LLC outside one federal reporting requirement. | Not a type of company and nothing to buy. Since August 2026 it describes nearly every US-formed LLC. What changed. |
| Trust-owned LLC | An ordinary LLC whose membership interest is held by a trust. | A combination rather than a type. The LLC is still an LLC. Full guide. |
The caveat that matters
Availability is state by state
Business structures are creatures of state law. What exists, who can use it, what it costs, and what it requires annually all differ depending on where you file.
- Several states restrict LLP registration to specified professional activities.
- PLLCs don't exist everywhere, and where they do, the eligible professions vary.
- Operating agreements are required in some states and not others.
- Annual report requirements differ, and a few states have none for LLCs.
- Filing fees and franchise taxes range widely enough to change the decision.
Any article handing you a single national answer, this one included, is simplifying to stay readable. Your state's filing office is the only source that's actually about you.
Common mistakes
What goes wrong most often
- Thinking a DBA protects anything. It's a name registration. Nothing more.
- Accidentally forming a general partnership. Two people going into business together create one without filing anything, complete with shared personal liability.
- Assuming nonprofit means tax-exempt. Two separate things, and the second takes an application.
- Picking a structure based on what someone else used. Their liability exposure, ownership, and tax position aren't yours.
- Treating formation as the finish line. The ongoing filings keep it alive. Entities rarely die dramatically; they mostly starve quietly over a missed annual report.
Related
Keep reading
Where NCC fits: if you know what you want, we'll form it. If you don't, we'll walk the options properly, including how each is taxed, and say when an attorney's opinion is actually worth buying. Formation support ->
Sources
Check our work
General education, reviewed 27 October 2026. NCC does not provide legal advice of any kind. Nothing here recommends a structure for you. Availability and requirements vary by state; verify with your own state's filing office, and take entity selection to a licensed attorney.
Read all that and still not sure?
That's a reasonable place to land, because the honest answer depends on facts about you. Tell us what the business does and who's involved, and we'll narrow it down with you.