A Series LLC is a single parent limited liability company that can hold any number of internal divisions, called series, with each series carrying its own assets, members, and liability shield. A lawsuit or debt tied to one series can reach only that series’ assets, leaving the parent and every other series untouched, provided you form and maintain the structure correctly. Real estate investors use this heavily, placing each rental property in its own series so a slip-and-fall at one building can’t threaten a portfolio of twenty others.
How the Internal Liability Shield Works
The parent entity, sometimes called the master or umbrella LLC, sits at the top. Beneath it, you create individual series that can each hold property, sign contracts in their own name, and sue or be sued independently. Under Delaware’s statute, the debts and obligations of one series are enforceable only against that series’ assets, not against the parent or any sibling series, as long as three conditions are met: the LLC agreement authorizes the series, the certificate of formation includes notice of the liability limitation, and the records account for each series’ assets separately from everything else in the organization.1Justia Law. Delaware Code Title 6 Chapter 18 Subchapter II – Section 18-215
The protection runs both directions. The parent’s creditors can’t reach into a properly maintained series, and one series’ creditors can’t grab assets owned by a sister series. That bidirectional shield is the whole reason the structure exists.
The shield collapses if you don’t maintain genuine separation. Courts can disregard the internal barriers through what’s sometimes called piercing the internal veil. The triggers mirror traditional veil-piercing: mixing funds between series, failing to keep separate books, or treating the series as interchangeable. Once a court decides the separation was a fiction, every asset in the structure becomes fair game for a single creditor.
Which States Allow Them
About 20 states and territories currently authorize the structure. The commonly used jurisdictions are Delaware, Texas, Illinois, Nevada, and Wyoming. Others with series statutes include Alabama, Arkansas, Indiana, Iowa, Kansas, Missouri, Montana, Nebraska, North Dakota, Oklahoma, South Dakota, Tennessee, Utah, and Virginia, along with the District of Columbia and Puerto Rico.1Justia Law. Delaware Code Title 6 Chapter 18 Subchapter II – Section 18-215 If your state isn’t on the list, you can still form a Series LLC in a state that allows them and register the parent as a foreign LLC at home, though recognition risks follow.
Statutes aren’t identical. Delaware distinguishes between protected series (internal only) and registered series (which file with the Secretary of State and get their own certificate). Illinois requires each series to file a separate Certificate of Designation at $50 per series.2Illinois Secretary of State. Guide for Organizing Domestic Limited Liability Companies The state you choose shapes your filing obligations, costs, and the strength of your shield.
How to Form One
File the Certificate of Formation
You form the parent LLC by filing a Certificate of Formation (Articles of Organization in some states) with the Secretary of State. The filing must include a specific provision stating the LLC is authorized to establish separate series with limited liability. In Delaware, this notice is sufficient whether or not any series yet exist, and you don’t need to name specific series in the filing.1Justia Law. Delaware Code Title 6 Chapter 18 Subchapter II – Section 18-215 Without that notice, the internal walls don’t exist no matter what your operating agreement later says.
Draft the Operating Agreement
The operating agreement is the document that actually brings individual series to life. It sets the rules for all series: how new ones are created, how members are admitted, how profits and losses are allocated, and how a series is wound down. Each time you create a new series, you add an amendment or exhibit naming that series, its purpose, its managers, its members, and its initial capital. In most states, creating a series is an internal act with no separate state filing. Illinois is the main exception, requiring a Certificate of Designation for each one.2Illinois Secretary of State. Guide for Organizing Domestic Limited Liability Companies
Get EINs
The parent LLC needs its own Employer Identification Number, obtained with IRS Form SS-4.3Internal Revenue Service. About Form SS-4, Application for Employer Identification Number (EIN) Whether each series also needs its own EIN depends on tax handling. A series that has employees, files its own return, or makes a separate tax election needs one. Even when not strictly required, giving each series its own EIN makes it easier to open dedicated bank accounts and reinforces the separateness the shield depends on.
Name Each Series Properly
Each series name should begin with the full legal name of the parent. If the parent is “Redwood Holdings LLC,” a series should read something like “Redwood Holdings LLC – Series 1.” Formats that bury or rearrange the parent’s name are often rejected and confuse anyone trying to identify the contracting party. Every contract, deed, bank account, and vendor agreement must identify the specific series. A lease signed by “Redwood Holdings LLC” alone, without naming the series, can undermine the argument that the series is a distinct unit.
How Taxes Work
Federal tax treatment is one of the murkier areas because the IRS hasn’t finalized regulations. Proposed regulations from 2010 would treat each series as a separate entity for federal income tax purposes, with each independently classified as a disregarded entity, partnership, or corporation. Those proposed regulations have never been finalized, leaving practitioners to work with general LLC tax rules and informal IRS guidance.
Under current rules, default classification follows ownership. A single-member LLC is a disregarded entity, with income and expenses flowing to the owner’s Form 1040, typically on Schedule C for business income or Schedule E for rental income.4Internal Revenue Service. Single Member Limited Liability Companies An LLC with two or more members defaults to partnership taxation, filing Form 1065 and issuing a Schedule K-1 to each member.5Internal Revenue Service. Limited Liability Company (LLC) Either way, income passes through to owners, avoiding corporate-level tax.
Each series can elect its own tax classification using Form 8832 for corporate or partnership status, or Form 2553 for S-Corporation status.6Internal Revenue Service. About Form 8832, Entity Classification Election A rental-holding series could stay a disregarded entity while an active consulting series elects S-Corp treatment to reduce self-employment tax. Once elected, the IRS generally requires five years before switching again. Any series treated as a separate entity for tax purposes files its own return, and shared costs like the registered agent fee need to be allocated across series on a documented, reasonable basis.
Keeping the Shield Intact
Formation is the easy part. The ongoing discipline is where most Series LLCs either hold up or quietly become useless.
Separate Money
Every series needs its own bank account. Money earned by Series A stays in Series A’s account. If Series B needs cash, that transfer has to be documented as a loan or capital contribution with proper terms, not casually moved. Separate books are mandatory. The Delaware statute requires records that “account for the assets associated with such series separately from the other assets of the limited liability company, or any other series thereof.”1Justia Law. Delaware Code Title 6 Chapter 18 Subchapter II – Section 18-215 Records may identify assets by specific listing, category, percentage, or any other objectively determinable method.
Getting banks to cooperate can be the hardest practical step. Many banks and credit unions are unfamiliar with the structure and will refuse to open an account for an individual series, insisting on treating the parent as the only entity. Shop for a bank that understands Series LLCs before you create the series. Some owners have better luck with banks in states where the structure is common.
Title Assets to the Specific Series
Every asset must be titled to the series that owns it. A property deed should name “Redwood Holdings LLC – Series 3” as the grantee, not just the parent. The same applies to vehicle titles, intellectual property registrations, and vendor contracts. Sloppy titling is probably the most common way owners accidentally collapse the barrier between series. If a court can’t tell which series owns an asset, that asset may be treated as the parent’s and exposed to any creditor of the whole organization.
Annual State Obligations
The parent is typically subject to annual reporting and franchise tax at the state level. In Delaware, every LLC owes an annual tax of $300, due by June 1.7Delaware Division of Corporations. LLC/LP/GP Franchise Tax Instructions In most states that single annual payment covers the parent, which is where the savings over multiple standalone LLCs come from. Illinois charges per series, so the savings are smaller there but still real compared to forming separate LLCs.
Boundaries: Multi-State Operations and Bankruptcy
Two situations stretch the Series LLC past its reliable zone. Both deserve a hard look before you commit.
If your Series LLC is formed in Delaware but owns property or does business elsewhere, you generally have to register the parent as a foreign LLC in that other state. The real question is whether the other state will respect the internal walls between series. States with their own Series LLC statutes are more likely to honor the structure. Pennsylvania, which has no series statute of its own, has passed a law requiring state courts to respect the liability protections of properly formed out-of-state Series LLCs. Many states have no statute or case law on the point at all, and a court in one of those states might treat all your series as a single entity, defeating the structure’s purpose. For properties in states with no clear recognition, a standalone LLC in that state is often safer even at higher cost.
Bankruptcy is the other open question. The federal Bankruptcy Code defines a debtor as a “person,” and the definition includes individuals, partnerships, and corporations without explicitly naming LLCs. Courts have generally accepted that a standard LLC qualifies, but whether an individual series counts as a separate “person” eligible to file on its own has no definitive answer. Illinois’ statute says each series “shall be treated as a separate entity,” which gives a bankruptcy court stronger footing. Delaware’s statute is less explicit, creating more ambiguity. There is also no clear precedent that the internal walls would survive inside a bankruptcy proceeding of the parent itself. If the parent goes bankrupt, a trustee could argue that all series assets belong to the parent’s estate. For owners protecting high-value assets, that risk alone pushes some attorneys to recommend separate standalone LLCs.
When This Structure Fits
A Series LLC works best when you’re managing multiple similar assets in the same state, especially rental properties. The savings are real. Instead of paying separate formation fees, annual reports, and registered agent fees for ten standalone LLCs, you pay once for the parent and handle everything else internally. For a real estate investor adding a property each year, the difference adds up fast.
It’s a poor fit when your assets or operations span states that don’t recognize the structure, when bankruptcy protection is a central concern, or when you need conventional business financing. Lenders often don’t understand Series LLCs; some will refuse to lend to an individual series or will demand personal guarantees that bypass the liability protection anyway. The limited case law also means you’re building on a foundation that hasn’t been fully tested. The body of precedent is growing, but anyone choosing this structure now should know it is still somewhat early.
For owners who decide the benefits outweigh the risks, the shield is only as strong as the operational habits behind it: separate accounts, meticulous records, properly titled assets, and an operating agreement that clearly defines every series.