How to Start a Solar Installation Business in Connecticut: PV and Solar Thermal Licenses

If you want to start a solar installation business in Connecticut, there is no single state business license to apply for. Connecticut has no general state business license. What you need instead is a trade license from the Department of Consumer Protection (DCP) for the work you do, a business entity registered with the Secretary of the State, a sales tax permit if your work is taxable, and a town permit for each installation. This guide walks through that sequence in order, with the fees the agencies publish and clear flags where you need to confirm a figure with the agency.

This article is informational, not legal or tax advice. Entity choice, tax treatment and licensing questions depend on your specific facts. Talk to a Connecticut business attorney and a CPA before you form the company or sign your first customer contract.

What You Need Before You Start

• A proposed business name, checked for availability with the free Business.CT.gov business records search
• A Connecticut registered agent: a Connecticut resident age 18 or older, or a business entity registered with the Secretary of the State, with a physical Connecticut business address
• Written proof of your solar experience and training, such as employment records or apprenticeship records
• A licensed electrical contractor or an E-1 or E-2 electrician lined up for any connection work (see Step 7)
• A budget for filing and registration fees: $120 for an LLC Certificate of Organization, $80 for the LLC Annual Report, $100 for a Sales and Use Tax Permit, and $20 for a trade name certificate if you operate under a name other than your legal name
• Insurance quotes, including general liability coverage
• A list of the towns where you plan to work, since permit rules are set locally

Step 1: Choose Your License Track

Connecticut licenses solar work in four classes. The PV classes cover photovoltaic or wind generation systems that run up to a point immediately inside a structure or adjacent to the end use. The ST classes cover solar thermal work.

• PV-1, limited solar electric contractor: the contractor-level PV license
• PV-2, photovoltaic journeyperson: must work for a licensed contractor, and only for a licensed electrical contractor
• ST-1, solar thermal contractor: the contractor-level solar thermal license
• ST-2, solar thermal journeyperson: must work for a licensed contractor

If you plan to run the business and contract directly with customers, the contractor classes (PV-1 and ST-1) are the ones that fit an owner-operated company. Confirm with DCP which class covers the work you plan to sell before you build your offer around it.

Step 2: Meet the Experience Requirements

PV-1 and ST-1 require two years as a solar journeyperson or equivalent experience and training. This is the largest timing factor in the whole process. Document every project from the start: dates, system types, your role and the employer's name. Reconstructing years of job history after the fact is slow and easy to get wrong.

PV-2 and ST-2 require a registered apprenticeship or equivalent training. If you hire crew for these classes, review their apprenticeship records before you put them on a job.

Step 3: Apply to DCP

Apply through DCP Occupational and Professional Licensing. DCP covers the PV classes under its electrical license application and the ST classes under its heating, cooling and sheet metal work application. Only individuals can apply, and company applications are not accepted. Every applicant must pass an exam, and the exam vendor charges separate fees. The non-refundable application fee is $150 for a contractor license (PV-1 or ST-1) and $90 for a journeyperson license (PV-2 or ST-2). DCP does not pre-approve or review applications before you submit them.

Licenses renew every year. PV licenses expire on September 30 and ST licenses on August 31. The renewal fee is $150 for a contractor and $120 for a journeyperson. Confirm current amounts with DCP at [email protected] before you budget. Because the license is issued to you as an individual, also ask DCP how your business name should appear on contracts and permit applications.

Step 4: Form Your Business Entity

File your formation document with the Secretary of the State through Business.CT.gov. Formation is a registration, not a license, and it does not replace your DCP license.

Structure	Formation document	State filing fee	Yearly filing
LLC	Certificate of Organization	$120	Annual Report, $80
Corporation	Certificate of Incorporation	$250	Organization and First Report, $150, then Annual Report, $150

An LLC name must include 'Limited Liability Company' or an abbreviation such as 'LLC' or 'L.L.C.', and it must be distinguishable on the record from names already registered or reserved. A name reservation costs $60 and holds the name for 120 days. Expedited service costs $50 per transaction and is completed within 24 hours of receipt, but it is available only for online filings. The state says most online filings are accepted automatically, so expedited service is usually unnecessary.

Step 5: Appoint a Registered Agent

Every LLC and corporation formed in Connecticut must appoint and continuously maintain a registered agent to receive legal and official correspondence. The agent's business address must be a usual place of business in Connecticut that is customarily open during normal business hours with an authorized person present. A post office box or commercial mailbox does not qualify. A home address can meet this test only if it meets that standard, so check before you list it. Agent information is confirmed each year when you file the Annual Report.

Step 6: Register for Taxes

For LLCs, Connecticut has no franchise tax or annual privilege tax. An LLC taxed as a partnership or S corporation may elect the optional Pass-Through Entity Tax with the Department of Revenue Services (DRS). The election is annual and irrevocable for that year. An LLC treated as a corporation pays the Corporation Business Tax: 7.5% of apportioned net income with a $250 minimum, plus a capital base tax being phased out (0.16% for 2026, 0.11% for 2027, none from 2028), plus a 10% surtax for companies with $100 million or more of total income or filing in a combined unitary group.

If you sell taxable goods or services, you need a Sales and Use Tax Permit from DRS. The registration fee is $100, and you must display the permit at each location. The state sales tax rate is 6.35%. Whether a particular installation, equipment sale or service contract is taxable is a question for DRS and your CPA. Check the DRS sales tax information page before you write sales tax into your bids.

Step 7: Stay Inside the Electrical Boundary

This is the step most often gotten wrong. Under the Electrical Work Examining Board, PV license holders may not connect to any existing panel, junction box, wiring, circuit or utility meter. An E-1 or E-2 electrician must do that work. Your PV scope covers the array and the equipment up to that boundary, and the electrician covers the connection.

Build this into every bid. Price the E-1 or E-2 work as a separate line or subcontract it, and name who performs the connection in your contract and permit paperwork.

Use the DCP class names on proposals, permits and invoices: PV-1, PV-2, ST-1 or ST-2.

Step 8: Get Local Permits and Approvals

Connecticut has no county government, so there is no county permit office to look for. Permits come from the town or city where the job is located, usually through its building department. Zoning and historic district rules can add requirements in some areas. Permit requirements, fees and turnaround times vary by town, so check each town before you quote a job there.

Utility interconnection is a separate process run by the electric utility that serves the property. Ask that utility for its interconnection steps before you promise a customer an activation date.

Step 9: Set Up Insurance and Staffing

Get general liability quotes before you sign your first contract, and ask each insurer what it requires for rooftop and electrical-adjacent work. If you hire employees, confirm your employer obligations, including workers' compensation, with your insurer and the state.

Step 10: Keep the Business in Good Standing

LLCs and corporations must file an Annual Report with the Secretary of the State every year. The LLC fee is $80, and the corporation fee is $150. Business.CT.gov shows each entity its own next due date in its account rather than a flat statewide deadline. Widely reported practice for LLCs is a January 1 to March 31 window, but confirm your date in your account. Put your DCP renewal dates on the same calendar: September 30 for PV licenses and August 31 for ST licenses.

Common Mistakes to Avoid

• Looking for a state business license. Connecticut has none. Your trade license and your entity filing are separate requirements.
• Connecting a PV system yourself. A PV license holder may not connect to an existing panel, circuit or meter. Hire an E-1 or E-2 electrician.
• Using a post office box as the registered agent address. It does not qualify.
• Searching for a county permit. Connecticut has no county government. Go to the town or city.
• Filing a trade name with the Secretary of the State. A trade name certificate is filed with the town clerk of the town where the business is primarily transacted, for $20.
• Staffing PV-2 or ST-2 workers on their own. Those classes must work for a licensed contractor.
• Missing the Annual Report. A missed filing can put your good standing at risk, so calendar it the day you form.

Tips for a Faster Start

• Start your experience log on your first day of solar work, not when you decide to apply.
• Check name availability before you pay for a name reservation.
• Send DCP all of your fee, renewal and class questions in one email.
• Ask your CPA about the Pass-Through Entity Tax election before your first tax year closes.
• Ask your electrician for a written scope that matches your bid, so the boundary is clear to the customer.

Expected Results

Working through these steps does not guarantee a license or a steady flow of jobs. It puts you in a position to operate lawfully and to bid work with clear terms. Realistic timing depends on your experience record, DCP processing and town permit schedules. The largest variable is the two-year experience requirement for PV-1 and ST-1. In practice, the experience record and the electrical arrangement may take more planning than the state filings do, so start on those first.

Next Steps

Form your entity, confirm your license track and fees with DCP, set up your tax registrations, and lock in your electrical subcontractor before you quote your first job. This article is informational, not legal or tax advice. Consult a Connecticut attorney for entity and contract questions and a CPA for tax treatment.