Series LLC
A Series LLC is a parent LLC organized into multiple sub-LLCs (called "series" or "cells"), each maintaining separate assets, members, and liability protection. A judgment against one series does not affect other series of the same parent LLC, providing internal asset separation without requiring multiple complete LLCs.
Definition and overview
A Series LLC is a parent LLC organized into multiple sub-LLCs (called "series" or "cells"), each maintaining separate assets, members, and liability protection. A judgment against one series does not affect other series of the same parent LLC, providing internal asset separation without requiring multiple complete LLCs. The concept is foundational to US business law and tax practice. Most founders encounter series llc either at formation, during major business changes, or in connection with compliance filings.
History and legal basis
Series LLCs originated in Delaware's 1996 LLC Act. The structure was initially developed for mutual fund and investment fund use, where each series represented a separate fund. The structure has since expanded to real estate investment, intellectual property holding, and other multi-asset business models. Sixteen states currently recognize Series LLCs.
When to use series llc
Series LLC typically applies in these situations:
- At formation. Many of these concepts are decided when the entity is first created.
- During growth stages. As businesses scale, the concept may become more relevant or change in application.
- Tax planning. Most concepts in this area have direct tax implications.
- Liability and asset protection. Many of these structures exist primarily to manage legal and financial risk.
- Investor and M&A activity. Funded startups and acquisition targets need precise compliance with these concepts.
How to set up or file
- Research applicable rules. Series LLC is governed by a combination of federal (IRS, FinCEN) and state law. Verify current rules.
- Gather required information. Most filings require entity details, identifying information, and supporting documentation.
- Complete the form or filing. Federal filings typically go to IRS, FinCEN, or USPTO. State filings go to the Secretary of State or applicable state agency.
- Pay any applicable fees. Federal fees vary; state fees range from free to several hundred dollars depending on filing type.
- Maintain documentation. Keep filed copies and supporting records for at least 7 years for tax purposes.
- Track ongoing compliance. Many concepts in this area trigger ongoing filing or reporting requirements.
Common mistakes
- Missing deadlines. Federal and state deadlines for filings related to series llc are strict. Missing them often results in penalties.
- Incorrect classification. Many concepts have multiple sub-types that affect treatment. Get the classification right at the start.
- Inadequate documentation. When something goes wrong, documentation determines outcomes. Maintain clear records.
- Ignoring state variations. US business law varies significantly state-to-state. What's true in Delaware may differ in California.
- DIY without verification. Series LLC can be DIYed, but mistakes are expensive. Verify with a professional when uncertain.
Costs and fees
Costs associated with series llc vary by type, state, and complexity. File.Business handles most series llc services as part of our compliance plans (starting at $99/yr); we pass through state and federal filing fees at cost. Compare specific cost breakdowns across all 51 jurisdictions using our cost-by-state calculators.
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Start my business Talk to a specialistFAQ
What is a series LLC?
A series LLC is one parent LLC that can hold multiple internal series, each able to own its own assets and, in states that recognize it, shield those assets from the liabilities of the others. Investors use it to isolate each property or line without forming many separate LLCs. We confirm your state allows it and set up the structure.
How does the series LLC shield work?
Each series can hold assets separately, so a claim against one series generally cannot reach another's assets, similar to having many LLCs under one filing. The catch is the shield is well established in statute but lightly tested in court, so keeping each series' assets and records separate is essential. We build it to be defensible.
Which states allow series LLCs?
Not all: a subset of states authorize the series LLC by statute, and the list has grown but is far from universal. Where your state allows it you form at home; where it does not, you form in a series state and register as a foreign LLC. We confirm your state's exact status first.
How is a series LLC taxed?
Federal treatment is still developing: the IRS has proposed treating each series as its own entity, so many owners file per series while others report under the parent, and states differ. We flag the current treatment and obtain each series its EIN where its activity requires one.
Is a series LLC cheaper than multiple LLCs?
Usually: you pay one state formation fee for the parent rather than a fee per series, which is the savings, though some states add a per-series charge and the bigger cost is disciplined record-keeping. Current figures are on the pricing page.
Is a series LLC the same as a holding company?
No: a holding structure owns separate subsidiary LLCs each with its own filing, while a series LLC keeps them inside one entity as series. The holding route is more widely respected across states; the series LLC is cheaper but less tested. We help you weigh which fits.
Can I add series later?
Yes: once the parent series LLC exists, you generally add a new series internally by documenting it under the master Operating Agreement, without a fresh state filing in most series states. Each new series should get its own records and often its own EIN. We show how your state expects it done.
Who should use a series LLC?
Commonly real estate investors holding several properties, or owners running multiple brands or lines who want to wall off each one's risk cheaply. It fits when you have several distinct risk buckets under one owner. We help you decide whether a series LLC or separate LLCs fit your situation and state.
Does File.Business form series LLCs?
Yes: we confirm your state authorizes series, file the certificate with the required series language, build the master operating agreement, and set up EINs and records per series, so the structure is legally real rather than just sub-accounts under one name.
How we deliver, end-to-end.
Four-step path from request to confirmation. State and IRS turnaround varies; our steps run in parallel where possible to compress the timeline.
Intake + scope
You tell us what you need through a short intake form (or a call for complex matters). We confirm scope, surface any gating issues (deadlines, missing documents, entity status), and quote any state fees that pass through at cost.
Prepare + verify
Our specialists draft the filing, verify entity details against state databases, run internal QA, and route any items needing your sign-off. You see drafts before anything gets submitted.
File with the authority
We submit directly to the state Secretary of State, FinCEN, IRS, USPTO, or whichever authority your filing requires. We pay state fees at cost and track the submission identifier in your account.
Confirmation + vault
Stamped certificate, IRS notice, or filing receipt arrives in your SOC 2 encrypted document vault the moment we receive it. Next filing deadline auto-added to your compliance calendar where applicable.
Built on the same infrastructure used by 220,000+ businesses.
SOC 2 Type II audited
Independent annual security audit covering access control, change management, incident response, and data handling. Current report on request.
All 51 US jurisdictions
Every state plus DC plus Puerto Rico - direct filings, not third-party reseller. We hold registered-agent qualifications in every state we operate.
Deadline guarantee
If we miss a filing deadline on a service you pay us to manage, we pay the state penalty. Specific to each plan and the filings it includes.
4.9 from 8,200+ verified reviews
Independently verified by Trustpilot + Google + our own NPS infrastructure. Customer success team within reach by email, chat, or phone.
60-day money-back promise
Change your mind in the first 60 days and we refund our service fee in full. State filing fees pass through at cost and are non-refundable once paid to the state.
E&O insured
Errors and omissions coverage protects you from service errors. Carrier and certificate available on request for enterprise clients.