Sole Proprietorship in Connecticut: How to Start One

A Connecticut sole proprietorship is the simplest way to start a business in the state. There's no formation document to file with the Secretary of the State, no annual report, and no separate business entity tax. You just start doing business under your own name (or a trade name), and you become a sole proprietor by default the moment you take money for goods or services. That simplicity is the appeal, and it's also where people trip up, because "simple" doesn't mean "no paperwork at all."

This guide walks through exactly what a Connecticut sole proprietor needs to do to operate legally: registering a trade name if you're not using your own legal name, getting an EIN, registering for state taxes, and picking up any industry-specific licenses. It's written for people asking how to start a sole proprietorship in Connecticut without hiring a lawyer for a straightforward setup.

What Is a Sole Proprietorship in Connecticut?

A sole proprietorship is an unincorporated business owned and run by one person, where there's no legal separation between the owner and the business. You report business income on your personal tax return, you're personally liable for business debts and lawsuits, and you don't have to file anything with the Connecticut Secretary of the State to create the business itself. Compare that to an LLC, which requires a Certificate of Organization ($120 filing fee) and an annual report ($80 a year) filed with the Secretary of the State. A sole proprietor Connecticut resident skips both of those.

What you do still have to handle: naming your business correctly, registering that name locally if it's not your own legal name, getting a federal tax ID if you plan to hire anyone, and registering with the Connecticut Department of Revenue Services if you'll collect sales tax. None of this creates a new legal entity. It just makes your existing business operate legally and correctly under Connecticut and federal rules.

What You'll Need Before You Start

Gather these before you begin the process:

A business name, either your own legal name or a trade name ("doing business as" name) you plan to operate under
Your Social Security Number, used until/unless you get an EIN
$20 in cash or check, for the Trade Name Certificate filing fee, payable to your town clerk
Government-issued ID, most town clerks want this when you file the Trade Name Certificate in person
A business address, home-based is fine for most service businesses, subject to local zoning
An idea of what you're selling, goods vs. services matters for sales tax registration
A separate bank account plan, you'll need your trade name filing and EIN (if applicable) to open one

How to Start a Sole Proprietorship in Connecticut: Step-by-Step

Step 1: Decide on Your Business Name

If you're going to operate under your own legal name (for example, "Jane Rodriguez Photography" where Jane Rodriguez is your actual name), you don't need to register anything with the town. If you're using any other name, even something close like "J. Rodriguez Photography" or "Rodriguez Creative," Connecticut treats that as a trade name that has to be registered locally.

Before settling on a name, search the Connecticut business records search to make sure you're not stepping on a name that's already registered as an LLC, corporation, or trade name in your area. This search is free and takes a few minutes.

Step 2: File a Trade Name Certificate (DBA) at Your Town Clerk

This is the one filing most sole proprietors in Connecticut actually need to make. Unlike LLC or corporation filings, a Connecticut sole proprietorship trade name is not filed with the Secretary of the State. It's filed with the town clerk in the Connecticut town where you primarily conduct business. The fee is $20, payable directly to the town clerk.

Requirements and process vary slightly by town, so call ahead or check your town clerk's website for their specific form and whether notarization or in-person filing is required. Some towns require you to appear in person with ID; others accept mail-in filings. You can find general guidance on trade names at Business.CT.gov's trade name article.

Step 3: Get an EIN from the IRS (If You Need One)

A sole proprietor with no employees can legally use their Social Security Number for tax purposes and skip the EIN. But most banks require an Employer Identification Number to open a business bank account, and you'll need one regardless if you plan to hire employees, open a Keogh or solo 401(k) retirement plan, or operate as anything other than a pure single-owner cash business. Applying is free directly through the IRS website and takes about 10 minutes online.

Step 4: Register with the Connecticut Department of Revenue Services

If you're selling taxable goods or certain taxable services in Connecticut, you need a Sales and Use Tax Permit from the Connecticut Department of Revenue Services (DRS). This carries a $100 registration fee, and you're required to display the permit at your place of business. Connecticut's state sales tax rate is 6.35%. You can register through the DRS sales tax portal.

If you have no employees and sell only non-taxable services, you may not need this step at all, but confirm with DRS rather than guessing, since taxability rules vary by service type.

Step 5: Check for Industry-Specific Licenses and Local Permits

Connecticut has no single general state business license that applies to every sole proprietor. Whether you need a license depends entirely on your industry. Cosmetologists, contractors, food service operators, childcare providers, and dozens of other professions are licensed through agencies like the Department of Consumer Protection, the Department of Public Health, or the Connecticut Insurance Department, often through the state's eLicense system. Start with the Business.CT.gov New Business Checklist to identify what applies to your specific business.

Don't forget local requirements either: zoning approval for a home-based business, a local health permit for anything food-related, or a building occupancy permit if you're leasing commercial space. These are handled at the town or city level, not the state.

Step 6: Open a Dedicated Business Bank Account

Nothing in Connecticut law requires a sole proprietor to keep separate bank accounts, but you should do it anyway. Mixing personal and business funds makes bookkeeping a mess at tax time and weakens your position if you're ever audited or sued. Bring your Trade Name Certificate, EIN (if you have one), and ID to open the account. Compare monthly fees and transaction limits across a few local Connecticut banks or credit unions before committing.

Step 7: Get Business Insurance

As a sole proprietor, there's no liability shield between you and your business. A lawsuit against your business is a lawsuit against you personally, including your personal assets. General liability insurance is worth pricing out even for a small operation, and it's required by some clients and commercial landlords before they'll sign a contract or lease with you. If you have even one employee, Connecticut requires workers' compensation insurance.

Step 8: Understand Your Ongoing Tax Obligations

As a sole proprietor, business income and losses pass through to your personal Connecticut income tax return, taxed at Connecticut's progressive rates ranging from 2% to 6.99% across seven brackets. You'll also owe federal self-employment tax on net earnings. Most sole proprietors need to make quarterly estimated tax payments to both the IRS and DRS rather than waiting until the annual filing deadline, since there's no employer withholding taxes on your behalf.

Common Mistakes to Avoid

Assuming a trade name filing creates legal protection. It doesn't register your name statewide, doesn't create a business entity, and doesn't shield your personal assets. It only satisfies the legal requirement to disclose who's behind a business name.
Filing with the wrong office. New sole proprietors sometimes look for a trade name form on the Secretary of the State's site and can't find one, because that filing goes to the town clerk, not the state.
Skipping the sales tax permit because "it's a small business." Size doesn't matter; if you're selling taxable goods or services, you need the permit regardless of revenue.
Not checking local zoning before working from home. Some Connecticut towns restrict certain home-based business activities, particularly ones with client visits, signage, or employees.
Waiting until tax season to think about estimated payments. Underpayment penalties can apply if you don't pay quarterly estimated taxes as income comes in.

Sole Proprietorship vs. LLC in Connecticut

A sole proprietorship is faster and cheaper to start since it skips the Secretary of the State entirely, but it offers no liability protection. An LLC requires filing a Certificate of Organization ($120), maintaining a registered agent, and filing an $80 annual report, but it separates your personal assets from business liabilities in most circumstances. Many Connecticut sole proprietors start this way to test a business idea with minimal cost, then convert to an LLC once revenue or liability exposure grows. If you're on the fence, that risk tolerance question, not the paperwork, should probably drive the decision.

What to Expect After You Start

Once your trade name is filed and any needed tax registrations and licenses are in place, you can generally expect to operate legally as a Connecticut sole proprietorship without further filings tied to the entity itself. Renewal requirements, if any, typically apply to specific licenses or permits rather than the trade name itself; check with your town clerk on whether your Trade Name Certificate has an expiration or renewal cycle, since practices can vary locally. Keep in mind that actual timelines, fees at the local level, and licensing requirements can shift, so confirm current details with your town clerk and the relevant state agency before you file.

Disclaimer

This article is for general informational purposes only and does not constitute legal or tax advice. Requirements, fees, and processing details can change, and local town clerk procedures vary across Connecticut. For guidance specific to your situation, consult a licensed Connecticut attorney or a CPA before making formation, tax, or licensing decisions.