Connecticut's contractor-licensing framework runs almost entirely through the Department of Consumer Protection (DCP), Occupational and Professional Licensing Division, with an additional Home Improvement Contractor registration for residential remodelers.
Trade-specific state licenses through DCP.
- Electricians: E-1 Unlimited Electrical Contractor, E-2 Unlimited Electrical Journeyperson, L-5/L-6 low-voltage, T-1/T-2 telecommunications, C-5/C-6 electronics, and others (10 types total) under C.G.S. Chapter 393. Source: Connecticut DCP Electrical License Types and Scope of Work (https://portal.ct.gov/dcp/occupational-and-professional-division/occupational--profess/electrical-license-types-and-scope-of-work).
- Plumbers: P-1 Unlimited Plumbing Contractor, P-2 Unlimited Plumbing Journeyperson, P-3/P-4 limited, plus gas and pipefitting credentials. Source: Connecticut DCP Plumbing Licenses (https://portal.ct.gov/dcp/occupational-and-professional-division/occupational--profess/plumbing-licenses-and-scope-of-work).
- Heating, Piping, Cooling, Sheet Metal: S-1/S-2 unlimited, D-1/D-2 limited domestic, B-1/B-2 heating and cooling, G-1/G-2 sheet metal, and others (20 types total). Source: Connecticut DCP Heating, Piping and Cooling License Types (https://portal.ct.gov/dcp/occupational-and-professional-division/occupational--profess/heating-piping-and-cooling-license-types-and-scope-of-work).
- EPA 608: federal certification applies to refrigerant work (https://www.epa.gov/section608).
Home Improvement Contractor (HIC) and New Home Construction Contractor (NHC) registration. Connecticut's Home Improvement Act (C.G.S. Chapter 400) and New Home Construction Contractors Act (C.G.S. Chapter 399a) require contractors performing residential home improvements or building new residential homes to register with DCP. HIC and NHC registrations require registration fees, participation in the Home Improvement Guaranty Fund, and written-contract disclosures. HIC registration is separate from trade licensing; it does not waive the electrician, plumber, or HVAC license. Source: Connecticut DCP Home Improvement Contractor (https://portal.ct.gov/DCP/License-Services-Division/License-Division/Home-Improvement-Contractor-Registration).
Local building permits. Connecticut enforces building and mechanical permits through local building officials under the Connecticut State Building Code. Permits are issued by the local building official in the municipality where the work occurs. Source: Connecticut State Building Inspector (https://portal.ct.gov/DAS/Office-of-State-Building-Inspector).
To operate as a trade contractor in Connecticut you generally need: the applicable state trade license (E-1, P-1, S-1 as applicable), HIC or NHC registration if performing residential work, formation documents filed with the Connecticut Secretary of the State if operating as an LLC or corporation (https://business.ct.gov/), a federal EIN from the IRS, and Connecticut Department of Revenue Services registration if you collect sales tax. Verify each requirement against current statutes and local rules before you assume you are compliant.