Guide
What is a SIC code?
A five-digit code you probably picked from a dropdown in about four seconds when you incorporated. It may be the reason your bank account application was refused.
What it is
SIC stands for Standard Industrial Classification. It is a five-digit code describing what your business does, recorded at Companies House and updated on your confirmation statement. Every UK limited company must have at least one; you can record up to four.
It exists so that government can classify economic activity. Nobody at Companies House checks whether yours is accurate.
Why banks care
Because it is the fastest machine-readable signal of what your business does, and it feeds directly into a provider’s risk appetite.
Every bank maintains a list of sectors it will not serve, or will serve only with enhanced checks. Some are obvious — gambling, crypto exchange, money service businesses, adult services. Others catch people entirely by surprise, including certain construction, security, import-export and second-hand goods classifications.
Your application is screened against that list before a human sees it. If your code is on it, you can be declined without ever discussing your actual business.
How to check yours
Search your company on the Companies House register. Your SIC codes are listed on the overview. Read the full description, not just the number, and ask honestly whether it describes what you actually do.
Two things to look for:
- Is it accurate? A software consultancy filed under "other business support service activities" is not describing itself well.
- Is it unnecessarily broad or risky? Codes covering financial intermediation, money handling or trading in used goods attract scrutiny even when your business is mundane.
How to change it
You update SIC codes on your confirmation statement, which you file at least annually — and you can file one early specifically to make the change. It is inexpensive and takes minutes.
The change appears on the public register once processed. Wait for that before reapplying to a bank, because the provider checks the live record rather than what you type in the form.
What to do if your code is genuinely high-risk
If the code accurately describes a sector that banks avoid, changing it is not the answer — misdescribing your business to obtain banking is a very bad idea and will surface later.
Instead, apply where there is appetite. Zempler accepts applicants the mainstream declines and, unusually for that corner of the market, holds a full banking licence so your balance is FSCS-protected. Some high-street banks will consider higher-risk sectors with enhanced due diligence and a clear explanation.
Sole traders
Sole traders do not have SIC codes, because they are not registered at Companies House. Providers ask you to describe your business instead — which means the free-text description matters even more. Be specific: who pays you, for what, how often, roughly how much.
Related
SIC codes are one of five common causes of refusal. The others are Companies House mismatches, unverifiable addresses, overseas directors and vague business descriptions. All are covered in why applications get declined.
Common questions
What is a SIC code used for?
It classifies what your business does for government statistics, and is recorded at Companies House. Banks also use it as a fast signal of your sector when screening account applications against their risk appetite.
Can a SIC code stop me opening a business bank account?
Yes. Every provider maintains a list of sectors outside its appetite, and applications are screened against it automatically. If your code sits on that list you can be declined without your actual business ever being discussed.
How do I change my SIC code?
Update it on your confirmation statement at Companies House. You can file one early specifically to make the change. Wait for the public register to update before reapplying to a bank, because providers check the live record.
Do sole traders have SIC codes?
No. Sole traders are not registered at Companies House, so there is no code. Providers rely on your written description of the business instead, which makes being specific much more important.
How many SIC codes can a company have?
At least one and up to four. Listing several can help describe a genuinely mixed business, but adding a higher-risk code you do not need can create problems with banking.
Next steps
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