Connecticut contractor licenses: what the state requires, trade by trade

Connecticut does not have one contractor license. It has a registration for people who do home improvement work for homeowners, a separate set of licenses for the regulated trades, and environmental licenses for pesticides and tree care. Most of it runs through the Department of Consumer Protection (DCP). This page walks through each, then covers the work that needs none of them. For the wider picture of starting here, see our Connecticut startup guide, and for how the national pattern works, read how to get a contractor license.

Home improvement registration comes first for most residential jobs

The Home Improvement Act, in Chapter 400 of the Connecticut General Statutes, defines home improvement as repair, replacement, remodeling or improvement of a home or rental dwelling, and names driveways, swimming pools, porches, garages, roofs, siding, insulation, sunrooms, flooring, patios, landscaping, fences, doors, windows, waterproofing, storm restoration and mold remediation. DCP's guidance excludes contracts under $200. DCP's own list adds painting to the examples.

The statute also says a "contractor" does not include a person whose home improvement contracts with all customers total $1,000 or less in any twelve consecutive months. That is a different line from DCP's under-$200 job exclusion, so read both before you decide you are outside the Act.

DCP lists what falls outside registration: work homeowners do on their own property, subcontracted work, work covered by a trade license, commercial property, contracts under $200, property maintenance such as snowplowing, mowing, pruning and cleaning, tree and shrub cutting and grinding, and new home construction. New homes have their own New Home Construction Contractor registration.

As listed in October 2026, the DCP application costs $220 (non-refundable) and requires general liability insurance of at least $20,000, with the carrier and policy number entered in the online application. You must also have your business entity registered with the Secretary of the State before you apply. The statute also sets a $100 annual payment into the Home Improvement Guaranty Fund, payable with the application or renewal fee. DCP's page does not say whether the $220 already includes it, so confirm the total before you pay. Registrations expire each year on March 31.

Your number goes on ads and contracts

Section 20-427 requires every registered contractor to state in each advertisement that they are registered and to include the registration number. That covers a website, a truck, a mailer and a Google ad. If you are building or updating a site, put the number in the footer and on every service page, a point we return to in how to get leads without Angi.

Section 20-429 makes a home improvement contract unenforceable against the owner unless it is in writing, signed by both sides, includes the date, your name, address and registration number, a notice of cancellation rights, and start and completion dates. Changes must also be in writing and signed. The contract also has to disclose other home improvement or new home construction businesses in which the owners have been involved during the previous five years. Every home improvement contract counts as a home solicitation sale, so the cancellation notice applies no matter where it is signed.

What happens if you work without registration

The statute spells out the consequences. Offering to make a home improvement without a current certificate is a class B misdemeanor under section 20-427(b)(5). The commissioner can also impose a civil penalty of up to $1,500 per violation after a hearing. Under section 20-427a, DCP can notify the Department of Motor Vehicles, which then does not issue registration for the contractor's commercial vehicles until the contractor is in compliance. Any violation of the chapter is also treated as an unfair or deceptive trade practice.

Electrical, plumbing and heating licenses are separate and personal

These trades are licensed by DCP at the individual level. Electrical, plumbing and pipefitting, and heating, cooling and sheet metal licenses each have a contractor license and a journeyperson license, and every applicant must pass an exam. DCP's pages list these figures as of October 2026:

For plumbing and for heating and cooling, a contractor applicant needs more than two years as a journeyperson or equivalent experience and training, and a journeyperson needs a Connecticut Department of Labor apprenticeship or equivalent experience. Only individuals can apply, not companies. DCP states plainly that Connecticut has no reciprocal agreements with any other jurisdiction, so an out-of-state license does not transfer on its own. A licensed trade holder working only within that license is exempt from home improvement registration under section 20-428, but the moment you step outside the trade, for example a plumber building a deck, registration applies.

If your goal is to hire licensed tradespeople rather than hold the license yourself, read how to become a licensed electrician and how to become a licensed plumber for how the licensing path usually runs.

Pesticides, lawn treatments and tree care run through DEEP

Connecticut has no general "lawn care license," but anyone who decides what pesticide goes on a customer's property needs a supervisory certification from the Department of Energy and Environmental Protection (DEEP). DEEP certifies supervisors by category, such as ornamental and turf work or general pest control, and the exam covers the categories you pick. DEEP also has a separate junior operator certification for people who apply products under a certified supervisor, and its page says the supervisory certificate is what lets a licensee buy restricted-use pesticides from a registered dealer.

As listed in October 2026, the supervisor exam fee is $200 for up to three categories, the written pass mark is 75 percent, and most categories add an in-person oral exam in Hartford. The license fee is $285 and the certification lasts five years. Renewal takes 12 continuing education credits per category. Our pest control license guide covers the general path.

Tree care is separate. Anyone advertising, soliciting or contracting to do arboriculture, meaning work for hire to improve fruit, shade or ornamental trees, needs a DEEP arborist license. Since October 1, 2013, arborist businesses must also register. Plain tree and shrub cutting and stump grinding are excluded from home improvement registration, but the arborist rule covers work for hire to improve the condition of trees, so ask DEEP whether your tree job falls under it.

Locksmiths and home inspectors

Locksmiths register with DCP. As listed in October 2026, the application is $200, renewal is $200, registrations expire on December 31 of even-numbered years, and applicants submit Connecticut State Police and FBI criminal history records. DCP defines the work as inspecting, installing, recombining, rekeying or repairing locks and locking devices.

DCP states that home inspectors must be licensed by the department. The application forms are on the DCP occupational and professional division site. This page does not repeat the details because the pages we could read did not list them, so check the current form.

Trades with no state license, and what you still need

For mowing, snowplowing, pruning and cleaning, DCP's own exclusion list takes them out of home improvement registration. That does not make the work tax free. Connecticut's Department of Revenue Services taxes landscaping and horticulture, janitorial services, window cleaning and exterminating, and the sales and use tax permit has carried a $100 one-time registration fee in third-party summaries, so confirm the fee on myconneCT. Our sales tax guide and the state sales tax table show how this fits together. A pressure washing, gutter or junk removal business should check whether any job becomes a permanent change to a home, since that would pull it into home improvement. This page found no separate state license for pressure washing or junk removal.

This page is general information, not legal advice. Connecticut rules and fees change, so confirm each point with DCP, DEEP or the Secretary of the State before you rely on it.

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