LLC name availability check: how to do it right, in 20 minutes

Most founders pick an LLC name, search their state's Secretary of State database, see no match, and assume they're clear. Twelve months later, a cease-and-desist letter shows up because the name conflicts with a federal trademark in the same industry. The state search felt definitive, but it only covered one of the four checks an LLC name actually needs. This post walks through all four, in the order that catches the most conflicts before you spend a dollar on filing fees.

If you want the broader view across all entity types (LLC, corp, sole prop, DBA), the complete business name availability guide covers the full picture. This post zooms in on the LLC-specific workflow.

Quick answer

An LLC name availability check is three separate searches, not one. You need (1) a state Secretary of State entity search to make sure no existing LLC or corporation in your state uses the same or a confusingly similar name, (2) a federal trademark search on USPTO's database to surface conflicts that the state will not catch, and (3) a domain plus social handle check to confirm the name is marketable. Your state SOS pass is necessary but not sufficient. Most rebrand horror stories happen because founders treated step one as the whole job.

The 3 checks every LLC name needs (state, federal, marketable)

There are three independent layers of risk when you pick an LLC name, and each one has its own database.

State entity match. Your state will not let you register an LLC with a name that conflicts with an existing entity registered in that state. This is what your state SOS search catches. It is the easiest layer because the state literally tells you yes or no when you file.

Federal trademark conflict. The U.S. Patent and Trademark Office issues federal trademarks that give the holder rights across all 50 states in a specific industry class. Your state SOS does not check this. A clean state search has zero bearing on whether you'd lose a trademark dispute. Federal marks beat state filings in court.

Marketability. Even if the name clears state and federal databases, the .com might be parked by a squatter, the Instagram handle might belong to an inactive account that the platform won't release, and the LinkedIn company page slug might already be taken. None of these will block your filing, but any of them can quietly cost you a year of SEO equity, a confused customer base, or a $20,000 domain purchase later.

Most founders run only the first check. That's the gap.

How to search your state Secretary of State (with state-by-state links)

Every state has a free business entity search tool. Find yours by Googling "[your state] secretary of state business search" and looking for the .gov result.

Here are the direct links for the 10 biggest states:

• California: bizfileonline.sos.ca.gov
• Texas: SOSDirect via sos.state.tx.us
• Florida: Sunbiz at search.sunbiz.org
• New York: apps.dos.ny.gov/publicInquiry
• Pennsylvania: file.dos.pa.gov
• Illinois: ilsos.gov/corporatellc
• Ohio: businesssearch.ohiosos.gov
• Georgia: ecorp.sos.ga.gov
• North Carolina: sosnc.gov/online_services/search
• Michigan: LARA at cofs.lara.state.mi.us

The search itself takes 30 seconds. Type the name. If you get exact-match results, your name is taken in that state and you'll need a different one. If you get no results, you're clear at the state level.

Two things to test that founders skip:

1. Search without the LLC suffix. "Acme Solutions LLC" and "Acme Solutions" are the same entity for conflict purposes. Drop the designator.
2. Try common variants. "Acme Solutions", "AcmeSolutions", and "Acme Solution" can all trigger a deceptive-similarity rejection at the time of filing. Search the variants too.

If the state search comes back clean, you're done with layer one. Move on.

Why a state SOS pass does not mean you are trademark-safe

Here is where most founders stop. They shouldn't.

Federal trademark law operates on a totally different system from state entity registration. The USPTO grants trademarks against specific classes of goods and services (there are 45 classes, called Nice Classes). A registered federal mark is enforceable across all 50 states for that class, regardless of what state you filed your LLC in.

What this means in practice: a company in Oregon can register the federal trademark "Bluepine" for software in Class 9. You can later form "Bluepine LLC" in Florida and your state SOS will approve it (Oregon's federal mark has nothing to do with Florida's state entity registry). Twelve months later, when you start selling software, Bluepine in Oregon's lawyer sends a cease-and-desist demanding you rebrand, surrender your domain, and transfer your social handles. You'll likely lose if it goes to court, because federal marks beat state filings.

The fix is to run a federal trademark search before you file your LLC. The full walkthrough lives in how to check if a business name is trademarked and the USPTO-specific tool walkthrough is in the free USPTO trademark search guide. Three searches every founder should run:

• Exact match. Type your proposed name with no modifiers. This catches direct hits.
• Word-stem match. Drop the most distinctive single word from your name and search that alone. "Bluepine" should be searched as "blue" stem too, because USPTO grants protection on the distinctive element.
• Phonetic match. Try common misspellings and homophones. "Bluepine" should also be checked as "blewpine", "blu pine", "bluepyne". USPTO grants protection against confusingly similar marks, not just exact matches.

For each hit, check the goods/services classes. A trademark for "Bluepine" in Class 25 (clothing) does not conflict with your Class 9 (software) use. Cross-class adoption is generally allowed unless the consumer-confusion test is met.

Most early-stage founders can clear this themselves in 30 minutes. For anything you plan to scale past $1M in revenue, get a trademark attorney to do a full clearance search before filing your own federal mark. The attorney will catch state-level common-law conflicts that the USPTO database does not surface.

NameClaim runs the USPTO federal search, plus the domain availability check across 13 TLDs, plus the Instagram, TikTok, and LinkedIn handle check, all in one search. That makes the federal-plus-marketability part of this workflow a ten-second job instead of an hour. Your state SOS check is still a separate manual step (no good tool covers all 50 SOS APIs).

Name reservation: when the $25 is worth it

Most states let you reserve a name for 30 to 120 days before filing your LLC's Articles of Organization. The fee ranges from $10 (Florida, sort of) to $75 (New York), with most states landing around $25 to $30.

Name reservation is worth the money when:

• You've cleared all three checks and you want to lock the name while you finish your operating agreement or wait on funding to clear before filing.
• You're operating in multiple states and want to reserve the name in your second state while you finalize your home-state filing.
• You're working with a trademark attorney on a federal application and want to prevent state-level squatting in the meantime.

Name reservation is a waste when:

• You're about to file the LLC anyway. The reservation buys you nothing if you file in the next two days. Just file.
• The name has any plausible federal trademark conflict. Reserve the state name and the conflict still gets you. Money wasted.
• You don't actually plan to start the business this year. Reservations expire, you'll pay again, and the name will likely still be free when you're ready.

Reservation is a tactical tool, not a step in the default workflow. Skip it unless you have a specific reason.

5 mistakes that cost LLC founders five figures

In rough order of frequency and cost:

1. Treating state SOS clearance as a green light. This is the biggest one and the reason this post exists. State SOS is layer one of four. The downstream cost of skipping the federal check is a forced rebrand, which routinely runs $10,000 to $50,000 for a year-old business when you account for new domain, new branding, new printed materials, lost SEO equity, and customer notification. The full picture of what actually happens lives in what happens if you use a trademarked business name, which is worth reading before you decide whether to skip the federal check.

2. Buying the .com before checking the trademark. Founders excited about a name often grab the domain first. If the trademark conflict surfaces later, you've spent $12 to $50 on a domain you can't legally use for your business. Worse, premium domains in the $1,000 to $10,000 range get bought before clearance all the time.

3. Filing in only one state when you operate in several. If your LLC operates in California but you formed it in Delaware, you need to also register as a foreign LLC in California, which requires a separate name availability check. The name being free in Delaware does not mean it's free in California.

4. Picking a name that's federally clear but descriptively weak. Names like "Best Software Solutions" might pass every check (no one trademarks descriptive phrases because trademark law requires distinctiveness), but you'll never own them in SEO, you'll never get them trademarked yourself, and you'll compete forever with the literal phrase in Google results. A clearance pass is not the same as a strong brand.

5. Reserving the name in your home state but not registering the federal trademark. State reservation gives you state-level rights only. Anyone in any other state can register the federal mark while you're paying $25 to hold the name in California. If you want the name long-term, file the federal trademark application in parallel with your LLC formation. The Intent-to-Use application costs $250 to $350 per class.

LLC name rules every state enforces (designators, restricted words)

Every state has its own rules but they overlap heavily. Here are the universal ones.

Designator required. Every state requires an LLC's legal name to end with a designator that identifies it as an LLC: "LLC", "L.L.C.", "Limited Liability Company", or some state-specific variation. Some states accept "Limited Company" or "LC". Your state SOS site lists the accepted designators.

Restricted words. Most states restrict words that imply a regulated profession or industry. "Bank", "Insurance", "Trust", "University", "Engineering", "Architecture", and "Medical" usually require additional licensing or proof of authority to use in your LLC name. Some states (like California) also restrict words like "Olympic" and "Corp" for non-corporate entities.

Profane or misleading names. Every state reserves the right to reject names it deems profane, deceptive, or against public policy. This rarely matters in practice but can come up for names that imply a connection to a government agency.

Distinctiveness from existing entities. As covered above, the name has to be sufficiently distinct from every existing LLC and corporation registered in that state. The standard is "deceptively similar", not "identical". "Acme Solutions LLC" and "Acme Solution LLC" might both get rejected.

If your state has a quirk worth knowing (New York's publication requirement is the big one, where LLC formation requires publishing notice in two newspapers for six weeks at total cost $1,000 to $2,500 in NYC), the state-specific posts cover those.

When to involve a trademark attorney

You can DIY all of this for most stages. The signals that mean it's time to involve an attorney:

• You're about to spend more than $5,000 on branding or marketing for the name.
• You've found a federal trademark conflict that might be in a different class but is close.
• You want to file your own federal trademark and the application has any non-trivial complication (descriptive elements, prior use claims, multiple classes).
• You've received a cease-and-desist letter or even an informal "please stop using" email.
• The name is your bet-the-company name and the cost of a forced rebrand later would be more than $50,000.

Initial trademark consultations are usually free. A full clearance search and federal application runs $500 to $1,500 in attorney fees plus the USPTO filing fee. Compared to the downstream cost of a forced rebrand or an actual lawsuit, it's the cheapest insurance policy in early-stage company building.