What is SIC Code?
A SIC (Standard Industrial Classification) code is a 5-digit number describing your company's main business activity, filed with Companies House.
Example
62020 = Information technology consultancy. 70229 = Management consultancy activities.
Key Dates
Included in confirmation statement
How SIC Code Works in Practice
A SIC code (Standard Industrial Classification code) is a 5-digit number that describes the nature of your company's business activity. Every UK company must report at least one SIC code to Companies House, and you can list up to four. The classification system was last updated in 2007 (SIC 2007) and is based on the European NACE system.
SIC codes are used by Companies House, HMRC, the Office for National Statistics, and other government bodies to classify businesses for statistical and regulatory purposes. They help the government understand the makeup of the UK economy and allow industry-specific analysis. HMRC also uses SIC codes to benchmark businesses -- if your reported turnover and profit look unusual for your industry code, it can trigger an enquiry.
Choosing the right SIC code matters more than most directors realise. An incorrect code can lead to being included in wrong industry benchmarks, receiving irrelevant correspondence, or in some cases, being subjected to regulations that do not apply to your business. Some insurance providers also check SIC codes when assessing risk, so an inaccurate code could complicate your business insurance.
You select your SIC code when you incorporate your company, and it is confirmed (or updated) each year as part of your Confirmation Statement. If your business activities change, you should update your SIC code at the next opportunity. The full list of SIC codes is published by Companies House and contains hundreds of options organised into broad sections like agriculture, manufacturing, construction, retail, professional services, and technology.
Step by Step
When you register a company with Companies House, the formation process requires you to select at least one SIC code that best describes your business activity. You can choose up to four codes if your company operates in multiple areas. The code is recorded on the public register and included in your Confirmation Statement each year.
To find the right code, you search the Companies House SIC code list using keywords related to your business. For example, a software developer might use 62012 (Business and domestic software development), while a marketing agency might use 73110 (Advertising agencies). If you cannot find an exact match, choose the closest option.
Each year when you file your Confirmation Statement, you confirm or update your SIC code. If your business has pivoted or expanded into new areas, this is the time to add or change codes. There is no cost to update your SIC code as part of the Confirmation Statement.
Practical Tips
- Spend a few minutes searching the Companies House SIC code list properly rather than picking a vague catch-all code
- If your business does multiple things, put your main revenue-generating activity as the primary SIC code
- Review your SIC code each year when filing your Confirmation Statement -- update it if your business focus has shifted
- Keep a note of your SIC code handy, as banks, insurers, and grant applications frequently ask for it
Common Mistakes to Avoid
- Choosing a generic code like 99999 (Dormant) when the company is actively trading, which can raise questions
- Not updating the SIC code when business activities change, leading to inaccurate records
- Selecting a code that does not match your actual activity, which can trigger HMRC benchmarking queries
- Confusing SIC codes with trade classifications used by insurance providers -- they may use different systems
Frequently Asked Questions
How many SIC codes can my company have?
You can list up to four SIC codes with Companies House. Most small companies only need one or two. List your primary activity first, and add secondary codes if you have significant revenue from other activities.
Does my SIC code affect my tax?
Not directly. SIC codes do not change your tax rates or obligations. However, HMRC uses industry benchmarks based on SIC codes to identify unusual returns. If your profit margins look very different from others in your SIC category, it could prompt HMRC to look more closely.
Where can I find the full list of SIC codes?
Companies House publishes the full SIC code list on gov.uk. You can search by keyword or browse by section. The condensed list used for Companies House filings contains around 730 codes covering all business activities.
Can I change my SIC code?
Yes. You can update your SIC code when filing your annual Confirmation Statement, or by filing a separate update at any time through Companies House. There is no fee for changing your SIC code as part of the Confirmation Statement.
What SIC code should I use for a consultancy?
The most common codes for consultancies are 70229 (Management consultancy activities other than financial management), 62020 (Information technology consultancy), and 74909 (Other professional, scientific and technical activities). Choose the one that best matches your primary consulting area.
Source: Companies House SIC codes: https://www.gov.uk/government/publications/standard-industrial-classification-of-economic-activities-sic
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