Search 731 Standard Industrial Classification codes to find the right code for your business. Used by Companies House, HMRC, and ONS.
The UK SIC 2007 system contains 731 five-digit codes, organised into 21 sections (A through U). These cover every type of economic activity from agriculture and mining to education and international organisations. Some older four-digit codes from SIC 2003 are still in use but are gradually being phased out.
Your SIC code is listed on your Companies House registration and your annual confirmation statement. You can also look it up on the Companies House register by searching for your company. If you are registering a new company, you must choose at least one SIC code during the incorporation process. Use the search tool above to find the right code by describing what your business does.
Yes, UK companies can register up to four SIC codes to describe different aspects of their business activities. The first code (SIC code 1) is considered the primary activity. You should add additional codes if your company operates in multiple sectors or carries out materially different types of work.
Using an incorrect SIC code can affect your tax classification with HMRC, your filing requirements, and how your company appears in industry statistics. It may also cause issues with insurance, regulatory compliance, and sector-specific obligations. You can update your SIC code at any time through your Companies House confirmation statement at no additional cost.
SIC 2003 used four-digit codes and was the standard until January 2008, when the UK adopted SIC 2007 with five-digit codes based on the EU classification NACE Rev. 2. SIC 2007 provides greater detail and better reflects the modern economy. Companies House now requires SIC 2007 codes for all filings, though some older companies may still show legacy SIC 2003 codes on their records until they file a new confirmation statement.