A Standard Industrial Classification (SIC) code identifies your company’s main business activities. You must provide at least one code when you form a new limited company.
Every limited company needs at least one SIC code. You can choose up to four, and should make sure they accurately reflect what your company actually does. For many IT contractors, 62020 – Information technology consultancy activities – is the most appropriate code.
SIC codes have been used since 1948. Companies House and other government bodies use them to group businesses by the type of work they do.
The classification has been revised several times over the years to reflect changes in the economy.
As a company director, it’s your responsibility to choose the right SIC code for your business, whether it is trading, non-trading or dormant. This guide explains how SIC codes work and how to choose the right one.
Does my limited company need a SIC code?
Yes. When you form a limited company, you must choose at least one SIC code describing the company’s business activity.
You won’t be able to complete the incorporation process without providing one.
Your SIC code also appears on the public Companies House register and must be confirmed or updated when you file your confirmation statement.
Where can I find the right SIC code?
For Companies House filings, use the searchable condensed list of SIC codes published by Companies House.
You should use a code from the Companies House condensed list. Using a code which isn’t on this list may result in your filing being rejected.
The Office for National Statistics published a new UK SIC 2026 classification in 2026, replacing UK SIC 2007 as the latest statistical classification. However, the new framework has not yet been implemented for Companies House filings, so companies should continue to use the codes available on the Companies House condensed list.
Most contractors form companies via their accountants or other intermediaries, so your accountant or formation agent may select a code on your behalf.
As a director, you (not your accountant) are responsible for the information filed at Companies House, so make sure the SIC code accurately describes what your company does.
Which SIC codes do IT contractors use?
Here are some commonly used codes for IT and technology businesses from the current Companies House list:
| SIC code | Description |
|---|---|
| 62012 | Business and domestic software development |
| 62020 | Information technology consultancy activities |
| 62030 | Computer facilities management activities |
| 62090 | Other information technology service activities |
| 63110 | Data processing, hosting and related activities |
62020 is likely to be the most appropriate code for many IT contractors and consultants, but you should choose the code which most accurately describes the work your own company carries out.
Your selected codes are visible to anyone who looks up your company on the Companies House register.
Do you need more than one SIC code?
If one code accurately describes what your company does, you don’t need to add any others. If your company has several distinct business activities, you can use more than one.
Companies House allows a maximum of four SIC codes.
For example, an IT contractor whose company also undertakes software development may decide that both 62020 (IT consultancy) and 62012 (software development) accurately describe the business.
What if I need to change my company’s SIC code?
If your company’s main activities have changed, you can update its SIC code by filing a confirmation statement.
You can update the code on your next confirmation statement, or file one sooner if you want to change it straight away.
Companies House can challenge or remove information it believes is inaccurate, so make sure your SIC codes continue to reflect what your company actually does.
What if I choose the wrong SIC code?
If you realise that you’ve selected the wrong code, you can correct it by filing a confirmation statement with the appropriate SIC code.
For an active company, don’t use a dormant or non-trading code simply because the company has temporarily stopped earning income. The code should accurately describe the company’s actual status and activities.
Companies House has specifically identified inappropriate use of dormant and non-trading codes by active companies as a common discrepancy.
Codes for dormant and non-trading companies
Dormant and non-trading companies still need to provide a SIC code.
The current Companies House codes are:
- 99999 – Dormant Company
- 74990 – Non-trading company
These descriptions are not interchangeable with an active company’s normal business SIC code. If your company starts trading, make sure its SIC code is updated to reflect its actual activity.
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