This guide is maintained as a current resource for July 2026 and covers only the laws of England and Wales. Information is for general guidance, not legal advice. Consult a qualified solicitor for advice specific to your situation.
A detailed guide explaining how to select SIC codes for UK company registration, including legal requirements, Companies House rules, step-by-step selection guidance, common classifications, and risks of incorrect coding under SIC 2007 for England and Wales company formation.
Standard Industrial Classification (SIC) codes are required when registering a company in the United Kingdom. They describe the nature of a business's economic activity and are submitted to Companies House as part of the incorporation process.
SIC codes are used for statistical classification by the Office for National Statistics (ONS) and for administrative purposes by Companies House. Selecting the correct code is a legal requirement for company formation and must be completed accurately to avoid rejection of filings or compliance issues.
What SIC Codes Are and Why They Matter
A SIC code is a five-digit number that identifies a company's main business activity. The UK uses SIC 2007, a structured classification system covering all sectors of the economy.
Companies House requires at least one SIC code for every limited company or LLP at incorporation and on annual confirmation statements.
Key functions include:
- Classifying business activity for public records
- Supporting statistical reporting by government bodies
- Assisting financial institutions in due diligence
- Ensuring regulatory transparency of company activities
Companies House uses a condensed SIC list. Only codes from this official list can be used for registration purposes. Using incorrect or non-existent codes can lead to filing rejection .
Legal Requirement to Provide SIC Codes
Under company registration procedures in England and Wales, SIC codes must be submitted:
- At incorporation (form IN01 for limited companies)
- For LLPs (LL IN01 equivalent form)
- Annually via the confirmation statement (CS01)
- When updating business activity details
Failure to provide accurate SIC codes may result in:
- Rejection of incorporation documents
- Filing delays
- Inaccurate public company records
- Compliance queries from Companies House
Even dormant companies must provide an appropriate code (typically 99999 for dormant activity) .
How to Select the Correct SIC Code
Step 1: Identify the company's primary activity
The primary SIC code should reflect the main source of income or intended business activity at the time of incorporation.
Examples:
- Software development: 62012 or 62020
- Construction: 41201 or 41202
- Retail (online): 47910
- Property letting: 68209
If the company has multiple activities, select the one most central to operations.
Step 2: Use the Companies House SIC list
Companies House only accepts codes from its official condensed SIC 2007 list. This list is structured by economic sector and must be used exactly as provided.
Incorrect or outdated codes from third-party sources may cause rejection of the application.
Step 3: Select up to four SIC codes
Companies House allows up to four SIC codes per company. This is useful where a business operates across multiple sectors.
Example:
A digital marketing agency offering software development and advertising services might use:
- 62020 – Information technology consultancy activities
- 73110 – Advertising agencies
- 62012 – Business and domestic software development
The first code is typically treated as the primary activity.
Step 4: Consider future business activities
SIC codes should reflect realistic intended activities, not speculative or unrelated sectors. However, they can be updated later through the confirmation statement.
Step 5: Confirm consistency with business description
The SIC code should align with:
- Company name (where relevant)
- Articles of association
- Business plan or intended operations
- Bank account and compliance documentation
Inconsistent classification can cause verification delays during banking or onboarding processes.
Common SIC Code Categories
Technology and digital services
- 62012 – Business and domestic software development
- 62020 – Information technology consultancy activities
- 63120 – Web portals
Retail and e-commerce
- 47910 – Retail sale via mail order or internet
- 47990 – Other retail not in stores
Property and real estate
- 68209 – Letting and operating of own or leased real estate
- 68320 – Management of real estate on a fee or contract basis
Construction
- 41201 – Construction of commercial buildings
- 43390 – Other building completion and finishing
Holding or dormant companies
- 64209 – Activities of other holding companies
- 99999 – Dormant company classification
Risks of Selecting the Wrong SIC Code
Incorrect SIC selection can lead to:
1. Filing rejection
Companies House may reject incorporation if codes are invalid or inconsistent with permitted classifications.
2. Compliance inconsistencies
Misclassification may raise questions during confirmation statement filings or company updates.
3. Banking and due diligence issues
Banks and financial institutions may request clarification if SIC codes do not align with declared business activity.
4. Tax and regulatory mismatches
HMRC may rely on SIC codes for statistical classification, and inconsistencies can lead to administrative queries.
Changing SIC Codes After Registration
SIC codes can be updated at any time through:
- The confirmation statement (CS01)
- Filing an updated statement of change
There is no formal penalty for correcting SIC codes, provided updates are made accurately and in line with actual business activity.
Practical Examples
Example 1: New e-commerce company
A startup selling clothing online would typically use:
- 47910 – Online retail
If it later expands into wholesale distribution, additional codes may be added.
Example 2: Property investment company
A company buying and renting residential properties might use:
- 68209 – Property letting and management
If it later adds estate agency services, additional classification may be required.
Example 3: Consulting business
A management consultancy might use:
- 70229 – Management consultancy activities (other than financial management)
Common Questions from our Readers
Do I need a SIC code to register a company?
Yes. Every UK limited company and LLP must provide at least one SIC code at incorporation.
How many SIC codes can I choose?
Up to four codes can be selected per company.
Can I change SIC codes later?
Yes. SIC codes can be updated through the confirmation statement or company update filings.
What happens if I choose the wrong SIC code?
The company can usually correct it later, but incorrect codes may cause delays or compliance queries.
Final Thoughts
Selecting SIC codes for company registration is a mandatory part of forming a UK company and plays an important role in regulatory classification and public record accuracy. The correct approach is to identify the company's primary activity, use the official Companies House SIC list, and ensure consistency with the business model.
While SIC codes can be updated later, accurate selection at incorporation helps avoid rejection, delays, and administrative complications. Businesses should treat SIC classification as an essential compliance step rather than a formality.
