What is an SIC code?

Q: How to choose an SIC code

To choose your SIC code, you can access the Standard Industrial Classification codes on the Companies House website. Each code is listed within its appropriate category, or you can use their search tool to identify the category of your business quickly and efficiently.

19th May 2026

Business owner smiling at the camera in her shop

A Standard Industrial Classification code (SIC code) is a five digit numerical identifier used to describe the main activities of a business.

Every UK limited company is required to provide at least one SIC code when incorporating or filing certain company documents. The purpose of the code is to give a clear indication of what the company does without needing a lengthy written description.

SIC codes are not unique to individual companies. Many businesses within the same industry will share the same classification code. The current SIC system used by Companies House is based on a standardised list of business activities covering thousands of industries and services.

As experienced third party formation agents who have helped countless businesses change SIC code, 99p Company Formations have outlined how to choose the right code for your new/adapting business.

How are SIC codes used?

SIC codes are used by Companies House to classify and record the activities carried out by UK businesses.

The information is then used by government departments and public bodies for a range of administrative and statistical purposes, including:

Tracking trends across different sectors
Producing economic and industry data
Understanding how many businesses operate within certain industries
Gaining a strong analytical understanding of the UK economy

When do you need an SIC code?

You will usually need an SIC code:

When forming a limited company
When filing your confirmation statement
When updating your company activities

If you are incorporating through 99p Company Formations, you will be asked to select the SIC code (or codes) that best match your business activities during the formation process.

Without at least one SIC code, your company registration cannot be completed.

How to choose an SIC code

To choose your SIC code, you can access the Standard Industrial Classification codes on the Companies House website. Each code is listed within its appropriate category, or you can use their search tool to identify the category of your business quickly and efficiently.

Choosing the right SIC code is important because it should accurately reflect the activities your company carries out.

It is also important to think about how your business is likely to operate long term, rather than focusing only on short term plans.

SIC code categories

There are hundreds of SIC codes available covering a wide range of industries, including:

Construction
Retail and e-commerce
Professional services
Healthcare
Technology
Hospitality
Manufacturing
Education
Real estate

The full list of official SIC code categories can be found through the Companies House SIC code guidance.

Because there are so many options available, it is common for directors to spend time reviewing multiple categories before deciding which best fits their business.

Common mistakes when choosing SIC codes

Although SIC codes appear straightforward, there are several mistakes that new business owners commonly make:

Choosing a code that is too broad: Some businesses select very general categories rather than identifying the activity they primarily carry out.

Selecting unrelated SIC codes: Adding multiple unrelated codes can make the company appear unclear or inconsistent.

Forgetting to update codes as the business grows: If your company evolves significantly, your SIC codes should evolve too.

Confusing products with services: Some directors choose retail codes when they actually provide consultancy or service based work.

Do you need multiple SIC codes?

You only need multiple SIC codes if a single code doesn’t summarise the complete offering of your business.

Many companies provide more than one service, particularly startups and growing businesses. In these cases, additional SIC codes can provide a more accurate representation of the company’s activities.

For example, a care provider may operate both residential support services and community outreach programmes. In that situation, they may use:

87200: Residential care activities for learning difficulties, mental health and substance abuse and
88990: Other social work activities without accommodation n.e.c.

How many SIC codes can you have?

You can choose up to four SIC codes for a limited company.

However, this does not mean you should automatically use all four. In most cases, businesses only require one or two codes.

Adding unnecessary or unrelated SIC codes can create confusion about what your business actually does and give you more information to keep track of.

Who can view an SIC code?

SIC codes form part of your company’s public record. Anyone searching your company on the Companies House register can see the SIC codes attached to your business.

When does a company not need an SIC code?

Most active limited companies require at least one SIC code. However, there are limited circumstances where a company may not need one. If you are operating/founding any of the following businesses, then you do not need an SIC code:

Sole traders
Limited partnerships
General partnerships
Limited liability partnerships

Do you need an SIC code for a dormant company?

Yes, dormant companies still require an SIC code. Even though the company is not actively trading, it remains registered with Companies House and still files annual confirmation statements. As part of this process, SIC codes may still appear as part of the company’s registered information.

In many cases, dormant companies retain the SIC code linked to their intended or previous business activity, but at the time of dormancy, you should change your SIC code to ‘99999’. This applies whether or not you plan to continue trading after the period of dormancy.

Can you change your SIC code?

Yes. It is relatively common for businesses to shift their focus over time and Companies House allows amendments to account for this.

All you need to do is file an early confirmation statement with your updated SIC code.

To do this, you can either use the Companies House WebFiling service or enlist the services of a third party formation agent. Online submissions cost £34 annually.

99p Company Formations supports businesses throughout the incorporation process, helping directors choose and change SIC codes based on their activities and long term business goals. For just £59.99, we handle the entire process on your behalf, helping you stay compliant without the risk of errors.