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What SIC code should a construction company use?
Find the right Companies House SIC code for a construction company, with examples for builders, electricians, plumbers, roofers and subcontractors.
By Callum Sommerton3 November 20263 min read
Choose the construction SIC code that describes what your company does. 41202 covers construction of domestic buildings and 41201 covers construction of commercial buildings. If you mainly provide a specific trade, start with its code. For example, an electrical installation company should look at 43210 and a roofing business should look at 43910.
Common construction SIC codes
SIC code | Companies House description | When to check it |
|---|---|---|
41100 | Development of building projects | You develop building projects. Compare with 41201 or 41202 if the company’s activity is construction. |
41201 | Construction of commercial buildings | You undertake commercial building projects as a builder. |
41202 | Construction of domestic buildings | You undertake domestic building projects as a builder. |
43110 | Demolition | Your company demolishes buildings or structures. |
43120 | Site preparation | Your business provides site preparation, such as clearing or preparing ground. |
43210 | Electrical installation | You install electrical wiring or systems. |
43220 | Plumbing, heat and air-conditioning installation | You install plumbing, heating or air-conditioning systems. |
43310 | Plastering | You provide plastering as a trade. |
43320 | Joinery installation | Your business installs joinery. |
43330 | Floor and wall covering | You fit floor or wall coverings, such as tiles. |
43341 | Painting | You provide painting services. |
43390 | Other building completion and finishing | Your completion or finishing work isn’t covered by a more specific entry. |
43910 | Roofing activities | You provide roofing services. |
43991 | Scaffold erection | You erect scaffolding. |
These are examples from the Companies House condensed SIC list.
How to choose when more than one code looks right
Describe what customers pay you for. “We install wiring in new homes” is more useful than “we work in construction.”
Compare the specific trade with the broader building code. If you’re engaged to install wiring, start with electrical installation. If your company takes on the domestic building project as a whole, look at domestic construction.
Add a code for a distinct business activity. A company can provide up to four codes. Start with the main activity and add another where it describes a separate line of work the company actually carries out. See Companies House guidance on keeping SIC codes accurate.
Three worked examples
A builder taking on house extensions. The company quotes for and delivers the whole extension, coordinating several trades. 41202 is the starting point to check.
An electrician subcontracting on house builds. The company invoices for electrical installation. 43210 describes the service even though the work happens on a residential building site.
A roofer who also sells scaffold erection as a separate service. Compare 43910 for roofing and 43991 for scaffold erection. If the company only uses scaffolding to do its own roofing jobs, start by checking the roofing code.
Describe your work in plain English in the free FOUNDRS SIC Code Finder, then check the suggested code against the Companies House list.
Is there a SIC code for a construction subcontractor?
Choose the code for your trade or service. A subcontracting plumber would look at 43220, while a subcontracting plasterer would look at 43310. The contract describes your relationship to the customer. The code describes the company’s activity.
The Construction Industry Scheme (CIS) is a separate HMRC process. If you work for a contractor or pay subcontractors for construction work, check the CIS rules for contractors and subcontractors.
How do I change a construction SIC code?
Check the code currently shown on the Companies House register. If it no longer describes what the company does, you can update it through a confirmation statement using a filing route that supports SIC changes. Read how to choose and update your SIC codes.
If you’re setting up a new construction company, register your limited company with FOUNDRS. The incorporation agent can help you describe your work and choose a code before you file.
