What is a SIC code?
A SIC code is a five-digit Standard Industrial Classification number that tells Companies House what kind of business activity a company carries out.
What a SIC code means
SIC stands for Standard Industrial Classification. It is a system the government uses to group businesses by activity, so that official statistics can show how many companies work in construction, software, hospitality and so on. Every UK limited company and LLP must give at least one SIC code when it is formed, and can list up to four.
The codes have five digits and run from broad to specific. For example, 62012 is "business and domestic software development", 56101 is "licensed restaurants" and 43220 is "plumbing, heat and air-conditioning installation".
Where it is used
- On the incorporation application to Companies House
- On each annual confirmation statement, where you confirm or update it
- On the public register, where anyone can see it
- By banks, insurers and lenders when assessing risk
Example
A founder sets up a company to run a café that also sells coffee beans online. She picks 56102 (unlicensed restaurants and cafés) as the main code and adds 47910 (retail sale via mail order houses or via the internet). Two years later the online shop has grown and she starts roasting beans for wholesale customers, so she adds 10830 (processing of tea and coffee) on the next confirmation statement, at no extra cost beyond the normal £50 filing fee.
Why it matters for your business
The SIC code does not decide how you are taxed, but it does shape how others see your company. A bank opening an account may ask questions if the code does not match what you say you do. Some insurers price policies by it. And a mismatch between your SIC code and your activity can prompt queries from HMRC or Companies House.
Special codes exist for companies that are not trading: 99999 (dormant company) and 74990 (non-trading company). If you are setting up a holding company or a dormant company, use the right one.
How to change it
You can change your SIC codes when you file your confirmation statement, which you must do at least once every 12 months. If the change cannot wait, you can file a confirmation statement early. Companies House keeps a searchable list of the codes so you can find the closest match.
Common questions
Yes, up to four. List the main activity first and add others that make up a significant part of what the company does. You do not need a separate code for every minor sideline or occasional piece of work.
No. SIC codes are only needed for companies and LLPs registered at Companies House. Sole traders describe their business activity on their Self Assessment return instead, and HMRC uses that description for its own records.