Single-member LLCs
The default structure for solo business owners. How the IRS treats it as a disregarded entity, why that's usually a good thing, what the liability shield actually requires, and the three mistakes that cause most veil-piercing cases.
Why solo owners pick the single-member LLC
The single-member LLC is the default structure for solo freelancers, consultants, e-commerce operators, and service businesses that don't need outside capital or multiple partners. It combines the liability protection of a corporation with the tax simplicity of a sole proprietorship. The owner pays one federal tax return (personal 1040) and runs one bank account (the LLC's), while the LLC itself provides a legal firewall between business activities and personal assets.
For the solo operator, the SMLLC is almost always the right structure once business activity is real. The main exception is a true side hustle earning under a few thousand dollars per year with zero liability exposure, where even a $129 state filing fee outweighs the benefits. For anyone earning $$20,000 or more from a business, the liability shield is worth the cost.
How the IRS taxes a single-member LLC
By default, an SMLLC is a "disregarded entity" for federal income tax. This means the IRS pretends the LLC doesn't exist for tax purposes and treats the owner as if they were a sole proprietor:
- Active trade or business: Report business income and expenses on Schedule C of the owner's personal 1040. Self-employment tax applies to net earnings.
- Rental real estate: Report on Schedule E. Rental income is generally not subject to self-employment tax.
- Investment LLC (holding stock, bonds, or royalties): Report the relevant income on Schedule B, D, or E as if the owner held the asset directly.
The LLC files no separate federal return by default. The owner uses their SSN (or EIN if they got one for banking) to file their personal return, and the IRS treats the business as if it belonged directly to the owner. This is the simplest possible tax arrangement for a solo business.
The SMLLC can optionally elect to be taxed as a corporation (C-corp via Form 8832, or S-corp via Form 2553). The S-corp election becomes relevant when net profit reliably exceeds $60,000 to $80,000 per year; below that, the administrative costs of running payroll typically exceed the self-employment tax savings. See LLC vs S-corp for the full analysis.
The liability shield, realistically
The liability shield is the whole reason to form an LLC instead of operating as a sole proprietor. For single-member LLCs specifically, courts scrutinize the shield more carefully than for multi-member LLCs, because the owner and the business are one person and one pocket. "Piercing the corporate veil" is more common for SMLLCs than for multi-member ones, particularly in states with older LLC statutes.
The shield works if the LLC looks like a real separate entity. It fails when the LLC looks like a sham. Three behaviors signal sham to a court:
Commingling funds
The single biggest veil-piercing trigger. If the LLC's bank account pays for groceries, or the owner's personal card pays for business inventory, the accounts are commingled. A court can treat the LLC as the owner's alter ego and reach personal assets for business debts. Keep separate accounts always, with no exceptions.
Signing contracts personally
Contracts should be signed "[Name], Manager/Member of [LLC Name]," not just "[Name]." If you sign a vendor contract in your personal name even though you're acting for the LLC, a court can argue the contract is with you personally and the LLC's shield doesn't apply. Every business contract, lease, loan, and formal document: sign in the LLC's name with your title.
Undercapitalization
An LLC with no real capital (no bank account balance, no assets, no insurance) that takes on significant debt or liability risk can be pierced on undercapitalization grounds. Keep enough working capital in the LLC to reasonably cover its operations. For businesses with real liability exposure (retail, products, contractors), maintain general liability insurance as additional protection.
Missing formalities
State annual reports unfiled, registered agent lapsed, operating agreement non-existent, no documented major decisions. Each missed formality is a piece of evidence that the LLC isn't being treated as a real entity. Set calendar reminders for annual filings and maintain simple written records of LLC decisions.
Must-haves for a single-member LLC
- Separate business bank account
Non-negotiable. The single most important thing you can do to protect the liability shield. Banks require an EIN to open the account, which is why every SMLLC should get an EIN even though federal tax rules don't require one.
- EIN from the IRS
Free, online, takes 15 minutes at irs.gov. Needed for the bank account, for any S-corp election, for hiring employees or contractors, and for filing 1099s. Never pay a third-party service for an EIN; it's free directly from the IRS.
- Operating agreement
Required by statute in CA, ME, MO, NY. Recommended everywhere else. Even a 3-page single-member agreement signed and dated by the owner is meaningful evidence of entity separateness. Most formation services include a free template.
- Business insurance
General liability insurance for any business with customer exposure (product sales, service delivery, client premises). Errors and omissions insurance for consulting and professional services. Budget $400 to $1,500/yr depending on industry. Insurance is the backstop if the veil ever fails.
- Registered agent
Every state requires one. You can be your own if you live in the state and have a physical address. Otherwise, a commercial service runs $99 to $249/yr. See the RA pillar for the full comparison.
- Annual report and state taxes
File on time every year. Missing annual reports is how most SMLLCs get administratively dissolved, which kills the liability shield. Calendar the due date and treat it with the same seriousness as personal tax filing.
Single-member LLCs and state-specific quirks
California: $800 FTB minimum
Every California SMLLC owes $800 per year in franchise tax to the Franchise Tax Board, whether it makes money or not. This is the biggest ongoing cost of any SMLLC in the US. See California formation.
New York: publication requirement
New York SMLLCs have to publish formation notices in two newspapers for six consecutive weeks. County-determined costs range from $500 to $1,800. Unique to New York. See New York formation.
Delaware: $300 flat annual tax
Delaware charges a flat $300 annual LLC tax regardless of income. No separate annual report fee. For a non-Delaware resident's SMLLC, the math rarely justifies Delaware unless you're holding IP or have other specific reasons. See Delaware formation.
New Mexico: $0 annual cost
New Mexico has no annual report requirement and no franchise tax. $50 formation fee and then nothing recurring from the state. The cheapest SMLLC to maintain in the country. See New Mexico formation.
Wyoming: anonymous SMLLC
Wyoming allows SMLLCs with no member disclosure on the public record. Combined with a commercial registered agent, this is the simplest path to an anonymous SMLLC. See anonymous LLC.
Tennessee: per-member annual report
Tennessee SMLLCs pay the $300 minimum annual report fee. The per-member fee only kicks in above 6 members, so single-member LLCs hit the floor. Still expensive relative to most states.
Common mistakes solo LLC owners make
- Never opening a separate bank account. Operating out of a personal checking account makes the LLC invisible legally and kills the shield.
- Paying personal expenses from the LLC. Buying groceries on the business card, even once, is commingling. Reimburse yourself cleanly through payroll or owner's draw instead.
- Signing in personal name. Every contract the LLC signs should be in the LLC's name with a title. Otherwise the contract might be treated as the owner's personal obligation.
- Electing S-corp too early. At $40K profit, the $2,000/yr in payroll + tax prep overhead exceeds the SE tax savings. Wait until profit is reliably above $60-80K.
- Letting the annual report lapse. Admin dissolution breaks the shield retroactively for the period you were out of good standing.
- Skipping insurance. The liability shield is a court-stage defense. Insurance pays for the actual lawsuit. You need both.
- Using the LLC as a hobby. If the LLC never makes money and the owner reports losses for multiple years without any profit motive, the IRS can reclassify the LLC as a hobby, disallowing loss deductions. Run the LLC like a business.
Frequently Asked Questions
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What is a single-member LLC?
A single-member LLC (SMLLC) is an LLC with exactly one owner, called a member. Legally, it's the same kind of entity as a multi-member LLC, but the federal tax treatment is different by default. For federal income tax, the IRS treats an SMLLC as a "disregarded entity," meaning it doesn't file its own tax return. Business income and expenses flow through to the owner's personal 1040 on Schedule C (for active businesses) or Schedule E (for rentals). State tax treatment usually follows federal, with exceptions in a few states that tax LLCs separately.
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Is a single-member LLC the same as a sole proprietorship?
For federal tax, yes. For legal liability, no. A sole proprietorship has no separation between the business and the owner; every debt and lawsuit against the business is against the owner personally. A single-member LLC creates a legally separate entity. Contracts, debts, and lawsuits against the LLC do not automatically reach the owner's personal assets. The tax treatment matches sole prop, but the liability shield is what you're actually paying for. See LLC vs sole proprietorship for the full comparison.
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Does a single-member LLC need an EIN?
Not for federal income tax purposes (you can use your SSN), but yes in almost all practical scenarios. Banks require an EIN to open a business checking account. The S-corp tax election requires an EIN. Any LLC with employees needs one. Hiring contractors and issuing 1099s requires one. Opening a merchant account or processing credit cards requires one. The IRS gives EINs out free through irs.gov; never pay a third-party service for an EIN. See the EIN pillar for application specifics.
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What taxes does a single-member LLC pay?
By default, the same taxes as a sole proprietor: federal income tax on business profit via Schedule C, self-employment tax (15.3% on net earnings up to the Social Security cap), and the state's personal income tax (where applicable). Optional: elect S-corp treatment (Form 2553) to split income between salary and distributions, reducing self-employment tax on the distribution portion. See LLC vs S-corp for the math on when the election is worth the administrative overhead.
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Do single-member LLCs need an operating agreement?
Legally: yes in California, Maine, Missouri, and New York. Practically: yes everywhere. An SMLLC without an operating agreement looks like a sole proprietorship wearing an LLC costume. Courts use the operating agreement as primary evidence that the LLC is a real separate entity, not just a tax identity. Even a simple 3-page single-member operating agreement is meaningful protection against veil piercing. See the operating agreement pillar.
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How do I protect the liability shield as a single-member LLC owner?
Four practices matter most. First, keep the LLC's money and your personal money in completely separate bank accounts (never use the business account for personal expenses, never pay business bills from personal funds). Second, sign contracts in the LLC's name, not your personal name. Third, maintain an operating agreement even as a single member. Fourth, file any required annual reports and pay any franchise taxes on time. Courts pierce SMLLC veils most often when commingling, sloppy contracting, and missed formalities combine. Clean habits are the whole shield.
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Can a single-member LLC have employees?
Yes. The SMLLC is a separate entity and can hire employees like any other business. For employment tax purposes, the LLC is treated as a separate entity regardless of its income tax classification (this is a specific IRS rule for SMLLCs with employees). Get an EIN, register for state payroll taxes, and run actual payroll with withholding, W-2s, and Form 941 quarterly filings. A payroll processor like Gusto or QuickBooks handles this for $40 to $100/month.
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What if I get married or add a partner later?
Adding a second member converts the LLC from single-member to multi-member. Federal tax treatment changes from Schedule C (disregarded entity) to Form 1065 (partnership) automatically. You'll need a new EIN if you didn't already have one. The operating agreement has to be updated to add the new member, document their contribution, and specify profit-sharing. In community-property states, spouses who both work in an SMLLC can elect "qualified joint venture" treatment to keep Schedule C filing rather than switching to Form 1065. Talk to a CPA before adding a second member.
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Can a single-member LLC own a car or house?
Yes, an SMLLC can own personal property (cars, equipment) and real estate. For real estate held for rental income, putting the property in an LLC is standard asset protection. For primary residences or personal vehicles, LLC ownership creates complications (losing homestead exemptions, insurance complications, mortgage due-on-sale issues) that rarely justify the liability shield. The common rule: investment assets in the LLC, personal assets in personal ownership. See LLC for rental property for the real estate specifics.