Resources > UK company SIC codes explained: How to choose the right one for your business

UK company SIC codes explained: How to choose the right one for your business

When forming a UK limited company, one important step is selecting your Standard Industrial Classification (SIC) code. This code tells Companies House and HMRC what your business does, helping to classify your company correctly in official records.

Choosing the right SIC code is essential for compliance, credibility, and smooth company registration — and it’s easier than you might think when you know what to look for.

What is a SIC code?

A SIC code is a five-digit number that describes the main activity your company will carry out. Every UK limited company must include at least one SIC code when registering with Companies House.

These codes help government agencies understand the nature of your business, track industry trends, and ensure the right tax rules are applied. They also appear in your public company record — so it’s important to choose one that accurately reflects your work.

Why does the SIC code matter?

Your SIC code plays a bigger role than most people realise. Here’s why it matters:

• Legal requirement – You can’t complete your company registration without it.
• Helps HMRC understand your business – This affects tax communication and may determine if you’re eligible for industry-specific schemes.
• Creates a professional impression – Banks, partners, clients, and investors often check your SIC code when doing background research.
• Useful for funding and tenders – Public grants and contracts often require it to confirm what sector you operate in.
• Keeps your records accurate – A clear and correct code avoids confusion later, especially if your company grows or seeks investment.

How to choose the right SIC code

1. Start with your main activity

Think about what your business primarily does or how you’ll generate most of your revenue. This is the activity your SIC code should reflect.

2. Browse the official list

The UK SIC 2007 list (used by Companies House) includes hundreds of codes for everything from IT consultancy and retail to marketing and real estate. It’s okay if your activity doesn’t match one exactly — just choose the closest fit.

3. Use more than one if needed

You can provide up to four SIC codes if your business covers multiple areas. Just make sure the first one represents your main activity.

Common SIC code examples

Here are a few popular ones:

Still not sure? We’ll help you choose the most accurate SIC code as part of your company formation with Mint.

Can you change it later?

Yes — your SIC code isn’t locked in forever. If your business pivots or grows into new sectors, you can update your SIC code in your confirmation statement (filed annually with Companies House).

What about non-UK residents?

Whether you’re based in the UK or abroad, all limited companies must select a SIC code at the time of formation. At Mint Formations, we specialise in helping non-UK residents through this process with clear guidance and complete support.

We’ll help you get it right

Choosing the right SIC code is part of building a strong business foundation. At Mint Formations, we:

• Guide you to the correct code(s)
• Help you avoid mismatches or delays
• Support multi-sector businesses with more than one code
• Offer continued help if your activities change later

It’s all included in our formation services — so you can register your company confidently, with everything done right the first time.

Helpful links

• Company Formation Checklist – Everything you need to prepare for registration.
• Mint vs Companies House – Compare doing it yourself vs using experts like us.
• Requirements for UK Company Formation – Understand the legal and structural basics before you register.

Let’s form your UK company — with the right SIC code, the right structure, and no stress.
Get started with Mint Formations today.