SIC code 4521 covers general construction of buildings and civil engineering works businesses. With 236 active companies, this is a specialised niche within the UK business landscape. It falls under Section F (Construction) of the UK SIC 2007 classification system, which is used by Companies House to categorise all registered businesses.
See the full industry analysis on the General construction of buildings and civil engineering works industry page.
The general construction of buildings and civil engineering works sector shows high turnover: only 15% of the 1,623 companies ever registered under this code remain active. A 85% dissolution rate is significantly above the UK average, suggesting challenging market conditions or frequent business restructuring in this sector. With an average age of 52.4 years, companies in this sector tend to be well-established. This maturity reflects high barriers to entry and strong business continuity among surviving firms. This is a mature sector with deep roots: 71% of active companies were established before 1990. While 0% of companies formed since 2020, the sector's backbone consists of long-established businesses. Companies are geographically dispersed across the UK, with no single location dominating. The top three locations — LONDON, GLASGOW, MANCHESTER — together account for just 11% of the sector.
SIC code 4521 stands for "General construction of buildings and civil engineering works" under the UK Standard Industrial Classification (SIC 2007) system. It belongs to Section F — Construction. Companies use this code when registering with Companies House to indicate their primary business activity. The code is required for annual confirmation statements and is used by HMRC, ONS, and other government bodies for statistical and regulatory purposes.
There are currently 236 active companies registered under SIC code 4521 in the UK, out of 1,623 total registrations. This gives a survival rate of 15%, meaning 85% of companies registered under this code have since dissolved. These figures are based on Companies House data and updated regularly.
The top locations for general construction of buildings and civil engineering works companies (SIC 4521) are: LONDON (12), GLASGOW (8), MANCHESTER (7), NOTTINGHAM (6), LEEDS (6). Geographic concentration can reflect local economic conditions, industry clusters, or proximity to key markets and supply chains.
Formation rates for SIC 4521 have been moderate: 0% of active companies formed since 2020, compared to 0% in the 2010s. The sector appears stable, with a balanced mix of established and newer businesses.
Companies classified under SIC 4521 have an average age of 52.4 years. This indicates a mature sector where businesses tend to operate long-term.
Related SIC codes within the same division include: 45200 (Maintenance and repair of motor vehicles), 45112 (Sale of used cars and light motor vehicles), 45320 (Retail trade of motor vehicle parts and accessories), 45310 (Wholesale trade of motor vehicle parts and accessories). Companies may use multiple SIC codes if they operate across several of these related activities. When registering with Companies House, businesses should select the code that best represents their primary activity.
You can search for companies with SIC code 4521 (General construction of buildings and civil engineering works) using UVAGATRON's company explorer, which allows filtering by SIC code, location, and company status. Alternatively, Companies House offers a basic search on their website. Our platform adds risk intelligence, director networks, and signals from 50+ government databases to each company record.
Search, filter, and analyse 236 companies classified under this SIC code with AI-powered risk intelligence.
Data sourced from Companies House, HM Land Registry, FCA Register, and 50+ government databases. SIC classification follows the UK Standard Industrial Classification of Economic Activities 2007 (SIC 2007). Last updated: 2026-04-17.