Connecticut LLC Business Name Rules
Learn the rules for naming an LLC in Connecticut — required designators, restricted words, name availability search, trade names, and how to reserve your name with the Secretary of the State.
Bizee Editorial Staff
Editorial Team
Connecticut LLC naming rules at a glance
Filing fee: $120 (online filing via Connecticut Business One Stop)
Processing time: Typically 3–5 business days for standard online filing
State agency: Connecticut Secretary of the State — Business Services Division
Annual report due: Annually by the last day of the anniversary month of formation
State tax rate: No state-level LLC franchise tax; Connecticut imposes a Business Entity Tax (BET) of $250 every 2 years (subject to legislative changes — verify current status)
Connecticut LLC naming rules
Connecticut requires every LLC name to include a designator that signals its legal structure, be distinguishable from existing entities on file with the Secretary of the State, and avoid words that imply unauthorized banking, insurance, or trust activity. Your name also needs to clear a state business search before you file your Certificate of Organization.
Required designators for Connecticut LLC names
Every Connecticut LLC name must include one of the following designators to identify it as a limited liability company. This requirement applies to the legal name on your Certificate of Organization — not just your branding or marketing materials.
- Limited Liability Company (spelled out in full)
- LLC
- L.L.C.
- Limited Liability Co. ("Limited" may be abbreviated as "Ltd." and "Company" as "Co.")
If your LLC is formed to render professional services — things like law, medicine, or accounting — Connecticut requires a different designator. Professional LLCs must use "Professional Limited Liability Company," "P.L.L.C.," or "PLLC" in their legal name.
Distinguishability and name availability
Your Connecticut LLC name must be distinguishable from every other business entity already on file with the Secretary of the State. "Distinguishable" means the name can't be so similar to an existing name that it would confuse the public — a minor spelling variation or punctuation difference may not be enough.
The state's name availability check is the only way to know for certain whether your chosen name is open. Run the search before you file — if the name isn't distinguishable from an existing entity, the Secretary of the State will reject your Certificate of Organization.
Prohibited and restricted words
Connecticut restricts words that imply your LLC is a bank, trust company, or insurance company unless your business is actually authorized to operate as one. Using terms like "bank," "banking," "trust," or "insurance" in your LLC name without proper authorization can constitute an unfair trade practice under Connecticut law.
The general rule is that your name can't mislead the public about what your business does or what type of entity it is. If you're unsure whether a word in your proposed name triggers a restriction, talk to a legal professional before filing.
How to search for a Connecticut business name
Use the Connecticut Secretary of the State's Business Records Search tool to check whether your proposed name is available. The state instructs users to search on the exact name — so search the full name you plan to use, including the LLC designator.
A name that returns no results isn't automatically available — the Secretary of the State makes the final call when you file. But running the search first saves you from filing a Certificate of Organization that gets rejected. It's worth doing before you print business cards or sign a lease.
How to reserve a Connecticut LLC name
If you've found an available name but aren't ready to file your LLC yet, Connecticut lets you reserve it for 120 days. The reservation period starts on the day you file the reservation form with the Secretary of the State.
The reservation form requires the proposed name (including the LLC designator) and confirmation that the name is distinguishable from existing entities on file. A reservation holds the name for you — it doesn't form the LLC. You still need to file a Certificate of Organization before the 120 days expire.
Connecticut trade names and DBAs
Connecticut LLCs can do business under a name that's different from their legal name — this is called a trade name or DBA ("doing business as"). Unlike most states, Connecticut handles trade name registration at the local level, not the state level. You file a trade name certificate with the town clerk in each town where you conduct business.
The trade name certificate must include the trade name, the LLC's full legal name and address, and the address where the business operates — as required under Connecticut General Statutes § 35-1. Filing a trade name certificate with a town clerk doesn't give you exclusive statewide rights to the name and doesn't provide trademark protection. For that, you'd need to register with the U.S. Patent and Trademark Office.
Trademarks and service marks
A name that clears the Connecticut business search can still infringe on a federally registered trademark. State availability and federal trademark protection are separate systems — the Secretary of the State doesn't check trademark databases when approving your LLC name.
Before you commit to a name, search the USPTO's trademark database to check whether the name — or something confusingly similar — is already registered. If your LLC name infringes on an existing trademark, the trademark holder can take legal action even after your LLC is formed. A trademark attorney can help you figure out your exposure before you file.
FAQ
Use the Connecticut Secretary of the State's Business Records Search tool at service.ct.gov to check name availability. Search the exact name you plan to use, including the LLC designator. The tool shows existing entities on file — if your name isn't distinguishable from one of them, it won't be approved when you file your Certificate of Organization.
Yes, Connecticut has specific naming rules. Your LLC name must include a designator like "LLC," "L.L.C.," or "Limited Liability Company." It must be distinguishable from all other entities on file with the Secretary of the State. It can't include restricted words — things like "bank" or "insurance" — unless your business is authorized to operate in that capacity.
Yes. Connecticut LLCs can operate under a trade name (DBA) that differs from their legal name. You register a trade name certificate with the town clerk in each town where you conduct business — not with the state. The certificate must include the trade name, your LLC's legal name and address, and the business address. Filing locally doesn't give you statewide or trademark rights to the name.
Yes. Connecticut lets you reserve an available LLC name for 120 days by filing a name reservation form with the Secretary of the State. The 120-day period starts on the filing date. A reservation holds the name — it doesn't form the LLC. You still need to file a Certificate of Organization before the reservation expires to lock in the name.
The Connecticut entity search is the Secretary of the State's Business Records Search tool. It lets you look up existing businesses by name to check whether your proposed LLC name is already taken. Go to service.ct.gov and search the exact name you want to use. If a matching or similar name comes up, you'll need to choose something more distinguishable before filing.
Yes. A Connecticut professional LLC — formed to provide licensed professional services like law or medicine — must use "Professional Limited Liability Company," "P.L.L.C.," or "PLLC" in its legal name instead of the standard LLC designator. The same distinguishability and restricted-word rules that apply to regular LLCs also apply to professional LLCs.
No. The Connecticut business name search only checks state entity records — it doesn't check federal trademark registrations. A name can be available in Connecticut and still infringe on a registered trademark. Before committing to a name, search the USPTO's trademark database. If you're unsure about your exposure, a trademark attorney can help you figure out the risk before you file.
