What Are LLC Formation Documents? Articles, Agreements, EIN

The core LLC formation documents are the articles of organization filed with your state, an operating agreement kept internally among the owners, and an employer identification number issued by the IRS. Depending on how you want the business taxed and where it operates, you may also need a tax classification election form and a short follow-up report to the state. Together these documents create the entity, set the rules among the owners, and register the business with the tax authorities.

Here’s what each one does, when you need it, and what happens if you skip it.

Articles of Organization

The articles of organization is the one document you must file with the state to bring your LLC into existence. Every state requires it, though some call it a certificate of organization or certificate of formation. Filing creates the LLC as a separate legal entity, distinct from its owners.

The required information is usually minimal:

The LLC’s name, which must include a designator such as “LLC” or “Limited Liability Company.” States reject names already taken or too similar to an existing entity.
A registered agent: a person or company with a physical street address in the state who can accept legal documents for the LLC. A P.O. box won’t work. If the registered agent’s address is wrong and a lawsuit gets served there, a court can enter a default judgment against your LLC without you ever knowing about the case.¹
The management structure: member-managed (all owners run the business) or manager-managed (designated individuals handle operations while other owners stay passive).
The principal office address, which can differ from the registered agent’s address.

Some states also ask for the LLC’s purpose, its duration, or the names of initial members. Most states now default to perpetual duration unless you specify otherwise. Once approved, the articles become part of the public record, so get the details right the first time; amendments are possible but cost additional fees and processing time.

Filing fees range from about $35 to $500, with most states charging between $50 and $200. Massachusetts sits at the high end at $500. A few states tack on additional costs beyond the base filing fee, such as mandatory business license fees or initial member list filings.

Operating Agreement

The operating agreement is your LLC’s internal rulebook. Unlike the articles of organization, it stays with the company rather than being filed with the state. But private doesn’t mean optional. At least five states legally require LLCs to adopt a written operating agreement, and in every other state, operating without one leaves your LLC governed by whatever default rules the state legislature wrote, which rarely match what the owners actually intended.

A solid operating agreement covers the ground rules that matter most when things go sideways:

Ownership percentages: who owns what share of the company, and what each member contributed (cash, property, services) to get that share.
Profit and loss allocation: how money is split among members, which doesn’t have to follow ownership percentages if the members agree otherwise.
Voting and decision-making: which decisions require a simple majority, which require unanimous consent, and who has authority to bind the company in everyday transactions.
Buyout and exit provisions: what happens when a member dies, becomes disabled, goes through a divorce, retires, or wants out. Without these provisions, a departing member can throw the entire business into limbo.
Dissolution triggers: the circumstances under which the LLC winds down and how remaining assets get distributed.

This is where most do-it-yourself formations fall short. People file the articles, get excited about the business, and never write down the rules. Then a dispute erupts and there’s nothing to point to except state default statutes that neither owner has ever read. A court examining whether your LLC truly operates as a separate entity or is just an extension of you personally will look for this agreement. If it doesn’t exist, the liability shield gets much easier to pierce.

Even single-member LLCs benefit from an operating agreement. It documents the separation between you and the business, and banks often ask to see one before opening a business account.

Employer Identification Number

An employer identification number is a nine-digit number the IRS assigns to your LLC for tax reporting. You apply using Form SS-4, either online through the IRS website (which generates the number immediately) or by mail or fax.²

The application requires you to enter the LLC’s legal name exactly as it appears on your state formation documents. You’ll also identify a “responsible party,” which the IRS defines as the person who ultimately owns or controls the entity and directs the disposition of its funds. That person must provide their Social Security number or individual taxpayer identification number.¹ If the responsible party changes later, you have 60 days to notify the IRS using Form 8822-B.

The form also asks about your primary business activity and the number of employees you expect to hire in the next twelve months.¹ Most multi-member LLCs need an EIN regardless of whether they have employees, because the IRS treats them as partnerships for tax purposes. Single-member LLCs can sometimes use the owner’s Social Security number instead, but you’ll still need an EIN if you hire employees or owe excise taxes.³ As a practical matter, most banks require an EIN to open a business account, so nearly every LLC ends up getting one.

Tax Classification Election Forms

By default, a single-member LLC is taxed as a disregarded entity (all income flows through to your personal return), and a multi-member LLC is taxed as a partnership.³ If those defaults work for you, no additional filing is needed.

Choosing a different classification requires additional paperwork:

Form 8832 (Entity Classification Election) is filed when an LLC wants to be taxed as a C corporation. The election can take effect no more than 75 days before the form is filed and no later than 12 months after the filing date. If your LLC is fine with the default classification, you skip this form entirely.⁴⁵
Form 2553 (S Corporation Election) is filed when an LLC wants S corporation tax treatment, which can reduce self-employment taxes for owners who also work in the business. The deadline is no more than two months and 15 days after the beginning of the tax year the election takes effect, or any time during the preceding tax year. Miss this window and you’ll wait until the following tax year unless the IRS grants late-election relief.⁶

S corporation elections come with restrictions: no more than 100 shareholders, only individuals and certain trusts as shareholders, no nonresident alien shareholders, and only one class of stock.⁶ These rules matter less for a typical small LLC but become critical if you plan to bring in investors or have foreign co-owners. Choosing the wrong classification or missing the filing deadline is one of the costlier formation mistakes, because you can’t retroactively fix it without IRS approval.

Initial and Annual State Reports

Many states require a supplemental report shortly after formation, often called a statement of information or initial report, that updates the state on your LLC’s current leadership and address. Deadlines vary widely, with some states requiring it within 90 days and others within the first year. Failing to file on time can trigger penalties or even suspension of your LLC’s authority to do business.

After that, most states require ongoing annual or biennial reports. These are typically straightforward forms confirming the LLC’s address, registered agent, and the names of members or managers. Fees range from nothing in a handful of states to several hundred dollars, with some states also collecting a separate franchise tax alongside the report.

The consequences of ignoring annual reports escalate quickly. States first impose late fees, then move to administratively dissolve the LLC. Once dissolved, the company can’t legally conduct business, can’t bring lawsuits, and people who continue operating under the dissolved entity can be held personally liable for debts incurred during the dissolution period. Reinstatement requires filing all overdue reports and paying accumulated penalties and back taxes, and in some states is only available for a limited window of two to five years after dissolution.

Foreign Qualification Documents

If your LLC does business in a state other than where it was formed, that second state will likely require you to register as a “foreign LLC.” In legal terms, any LLC operating outside its home state is foreign to the other state. The registration, often called a certificate of authority or statement of foreign qualification, typically requires a copy of your articles of organization, a certificate of good standing from your home state, and a filing fee. You’ll also need to designate a registered agent with a physical address in the new state.

What counts as doing business varies, but generally includes having a physical office, employees, or ongoing client relationships in the state. Occasional sales into a state or passive investments there usually don’t trigger the requirement. Operating in a state without registering can expose you to fines, block you from using that state’s courts to enforce contracts, and create tax complications.

Beneficial Ownership Reporting

The Corporate Transparency Act created a federal requirement for many business entities to report their beneficial owners to the Financial Crimes Enforcement Network. When the law was first implemented, domestic LLCs were going to be required to file a beneficial ownership information report disclosing the individuals who own or control the company. As of March 2025, FinCEN issued an interim final rule that exempts all entities created in the United States from BOI reporting requirements.⁷ Only foreign companies registered to do business in the United States remain subject to the requirement.

FinCEN has indicated it intends to finalize this rule, but the regulatory position here has shifted multiple times. If you’re forming a domestic LLC right now, you have no BOI filing obligation, though the final rule could adjust the exemption’s scope, so it’s worth checking the current status before you assume it still applies.

1
Internal Revenue Service. Instructions for Form SS-4 (Rev. December 2025)
2
Internal Revenue Service. About Form SS-4, Application for Employer Identification Number (EIN)
3
Internal Revenue Service. Single Member Limited Liability Companies
4
Internal Revenue Service. Form 8832 (Rev. December 2013)
5
Internal Revenue Service. LLC Filing as a Corporation or Partnership
6
Internal Revenue Service. Instructions for Form 2553 (12/2020)
7
FinCEN. FinCEN Removes Beneficial Ownership Reporting Requirements for U.S. Companies and U.S. Persons