Do you need an operating agreement for your LLC?
Almost every state lets you form an LLC without ever writing an operating agreement, but only Missouri and New York legally require one by statute. You should write one anyway, even as a single-member LLC with no partners to argue with. An operating agreement is the document that proves your LLC is a separate business, not just you with a state filing, and it is what reinforces the liability shield that keeps a lawsuit or creditor from reaching your personal assets. Banks also routinely ask to see one before they will open a business account.
Does a single-member LLC need an operating agreement?
Yes, even with one owner. An operating agreement is not a partnership contract between multiple people, it is a governing document for the business itself: how it is managed, how money moves in and out, and what happens if you sell it, add an owner, or shut it down. A single-member LLC without one is relying entirely on your state's generic default rules, which were written for no business in particular and can work against you.
The clearest reason single-member owners still need one: courts scrutinizing whether an LLC's "corporate veil" (the wall between the business and your personal assets) should be pierced look for proof the LLC was actually run as a separate entity. An operating agreement, even a short one, is direct evidence of that separateness. Skipping it does not undo your liability protection automatically, but it removes one of the clearest pieces of evidence that you treated the LLC as real.
Is an operating agreement legally required?
In most states, no filing office checks for one and there is no legal penalty for not having one. Two states are the exception, by the actual text of their LLC statutes:
- Missouri requires it outright. Mo. Rev. Stat. section 347.081 states members "shall adopt" an operating agreement, and the law is written broadly enough that an oral or implied agreement satisfies it, a written one is just better evidence.
- New York requires it in writing. NY Limited Liability Company Law section 417(a) states members "shall adopt a written operating agreement," and it must be adopted before, at the time of, or within 90 days after filing the Articles of Organization.
California is a partial case. Corp. Code sections 17701.02(s) and 17701.10 define an operating agreement to include oral or even implied agreements among members, so in practice every California LLC is treated as already having one, whether or not anyone wrote it down. There is no separate step to "satisfy" the requirement beyond running the LLC at all.
Delaware and Maine are frequently listed alongside these three in blog posts and formation-service marketing, but that is not what their statutes say. Delaware's LLC Act, 6 Del. C. section 18-101(9), explicitly states an LLC "is not required to execute" its operating agreement, and defines the agreement as written, oral, or implied. Maine's statute, 31 M.R.S. section 1521, describes what an operating agreement governs but does not contain language requiring members to adopt one. Neither state's actual code mandates one. Treat any source that flatly lists Delaware or Maine as "required" states with caution.
| State | Legally required? | Must it be written? | Statute |
|---|---|---|---|
| New York | Yes | Yes, within 90 days of filing | NY LLC Law section 417(a) |
| Missouri | Yes | No, oral or implied counts | Mo. Rev. Stat. section 347.081 |
| California | Yes, but automatically satisfied | No, oral or implied counts | Corp. Code sections 17701.02(s), 17701.10 |
| Delaware | No, despite common claims | N/A | 6 Del. C. section 18-101(9) |
| Maine | No, despite common claims | N/A | 31 M.R.S. section 1521 |
| All other states | No | N/A | State LLC acts, no adoption mandate |
Source: state statutes cited above, verified against each legislature's official published code.
Why do you need one if it is not required?
Three practical reasons show up over and over, regardless of what your state's statute says.
- It backs up your liability shield. The entire point of an LLC is that a lawsuit against the business generally cannot reach your house, car, or savings. That shield is weaker if you never treated the LLC as its own entity. An operating agreement, kept with your other formation documents, is proof you did.
- Banks ask for it. Most banks want to see an operating agreement, alongside your EIN confirmation letter and Articles of Organization, before opening a business bank account. Some will open the account without one, but plenty will not, and you do not want to be writing one under time pressure at the counter.
- It overrides your state's default rules. Without an operating agreement, an LLC is governed entirely by its state's default LLC statute. Those defaults are generic and were not written with your business in mind. Common defaults you may not want: profits split strictly by ownership percentage regardless of who does the work, every member having equal management authority, and dissolution triggered by events you would rather ignore. An operating agreement lets you overwrite all of that with terms you actually chose.
What should an operating agreement include?
A simple operating agreement, even for a single-member LLC, should cover the following:
| Section | What it establishes |
|---|---|
| Ownership | Who owns the LLC and what percentage each member holds |
| Management structure | Whether the LLC is member-managed or manager-managed, and who can sign contracts, open accounts, or bind the business |
| Capital contributions | What each member put in (cash, property, or services) to start the business |
| Profit and loss allocation | How profits, losses, and distributions are split, which does not have to match ownership percentage |
| Voting rights | What decisions need a vote, and whether votes are by ownership share or one member, one vote |
| Adding or removing members | The process for bringing in a new owner, or what happens if one leaves, dies, or wants out |
| Dissolution | What events end the LLC and how remaining assets get distributed |
| Single-member specific language | An explicit statement that the LLC is separate from its owner, useful evidence for the liability shield |
Source: standard operating agreement provisions described in state LLC statutes, including Mo. Rev. Stat. section 347.081 and Corp. Code section 17701.10.
Do you need a lawyer to write one?
No, not for a straightforward single-member or simple multi-member LLC. A basic operating agreement is a template document: fill in the ownership, management, and distribution terms, sign it, and keep it with your other LLC records. It does not need to be filed with the state or notarized in most states. A lawyer becomes worth paying for once the situation gets more complicated: multiple owners with unequal contributions, outside investors, a buy-sell arrangement in case a member leaves, or an industry with specific licensing rules baked into ownership. For a single owner just formalizing the basics, a template is enough.
The flat truth: write one regardless of what your state requires
The legal-requirement question is mostly a distraction. Only Missouri and New York force the issue by statute, and California's requirement is automatically met the moment your LLC exists. But "not required" and "not worth doing" are different things. An operating agreement costs you an afternoon, protects the liability shield that is the entire reason you formed an LLC, and is often the difference between a smooth bank account opening and a delay. Write one before you open that account, not after.
Once your operating agreement is drafted, see how it fits into the rest of the setup on our step-by-step business formation checklist. And if you have not settled on an LLC in the first place, compare your options in LLC vs S-corp vs sole proprietorship before you write an agreement for the wrong entity.
Sources
- Missouri's operating agreement mandate and its "written or oral" definition: Missouri Revisor of Statutes, RSMo section 347.081.
- New York's written operating agreement mandate and 90-day adoption window: New York Senate, LLC Law section 417.
- California's operating agreement definition (oral, written, or implied) and scope: Cal. Corp. Code section 17701.02 and section 17701.10.
- Delaware's statement that an LLC "is not required to execute" its operating agreement: Delaware Code, Title 6, section 18-101.
- Maine's operating agreement provisions, which do not include an adoption mandate: Maine Revised Statutes, Title 31, section 1521.