SIC Code Accuracy: What UK Companies Must Know

SIC code accuracy has just become a live compliance issue, not a historic one. Companies House’s Compliance and Enforcement Service published new guidance on this on 28 May 2026, and it lands in the middle of a much bigger shift: enforcement powers introduced back in 2023 are now actively being used. If your organisation’s SIC code was set years ago and never revisited, this is the moment to check it, before Companies House does.

Why is SIC code accuracy suddenly a compliance issue?

Every UK company selects a standard industrial classification (SIC) code when it registers: a five-digit code describing what the business actually does. That requirement isn’t new, and it dates back well before 2023.

What’s changed is the enforcement environment around it. The Economic Crime and Corporate Transparency Act 2023 (c. 56) received royal assent in October 2023. However, it’s being rolled out in phases rather than all at once.

Companies House, the UK’s registrar of companies, is moving through that rollout right now, in 2026. The most visible example is mandatory identity verification for directors and persons with significant control. Existing office-holders must complete this by 18 November 2026.

SIC code accuracy sits within that same rollout. There’s no separate statutory deadline attached to correcting a code. However, Companies House’s May 2026 guidance makes clear the accuracy powers already apply, and are being actively used. In short, this is current, not historic.

What are the new powers, exactly?

Before this Act, Companies House had limited grounds to question what companies filed. Information went on the register largely on trust, and errors could sit there indefinitely unless someone happened to notice.

Under the new powers, Companies House can challenge, reject, or remove information that appears incorrect, inconsistent, or misleading. This applies at the point of filing, not only after the fact. As a result, a confirmation statement carrying an obviously wrong SIC code can now be queried, delayed, or sent back for correction.

In addition, this shifts the burden from occasional record-keeping to ongoing SIC code accuracy. It’s a small change in wording, but a meaningful change in what’s expected of a compliance function.

What actually counts as a mismatch?

The most common problem Companies House flags is simple: a company is trading, but its SIC code still says otherwise.

Codes 99999 (dormant) and 74990 (non-trading) exist for a reason. Every company needs at least one SIC code, even a dormant shell entity. The trouble starts when an actively trading business keeps one of these codes long after operations begin.

Meanwhile, this is one of the most frequent discrepancies Companies House sees, and precisely the kind of gap its new powers are designed to catch. If an entity has moved from dormant to active, or changed direction entirely, the code on file should move with it.

Why does this matter beyond the register itself?

SIC code accuracy isn’t only about satisfying a regulator. Investors, lenders, and funding bodies use these codes to work out what a company does and whether it fits their criteria.

A mismatch, say, active trading shown as dormant, or simply the wrong sector, can create confusion at exactly the wrong moment. It may delay a loan application or complicate due diligence.

In addition, there’s a wider dimension worth knowing about. SIC code data feeds into HMRC (the UK tax authority) and the Office for National Statistics, which tracks industry trends and informs economic policy. Accurate codes across the register mean better data for everyone, including the sector-level analysis that may eventually affect your business.

How do you check and maintain SIC code accuracy?

Start with what’s already on file. The Find and update company information service shows the SIC code registered against any company, including yours.

There are more than 600 SIC codes to choose from, grouped into 21 main industry categories. If a business genuinely operates across several activities, it can select up to 4 codes rather than forcing everything under one heading.

Companies House publishes a condensed list to narrow the search. If the description still feels imprecise, it’s worth checking how comparable businesses have classified themselves on the same public register.

Updating an inaccurate code happens through a confirmation statement. Helpfully, the annual fee is only charged once within any 12-month payment period, so correcting a SIC code doesn’t mean paying twice if a statement has already been filed that year.

Which three questions should you ask before your next filing?

A short internal check now can save a filing delay later.

• Are you actively trading, and does your SIC code reflect this rather than showing dormant or non-trading status?
• Has your business activity changed since incorporation, or since you last reviewed the code?
• Does the code you hold actually describe what the company does, closely enough that a lender or investor would recognise it?

If the answer to any of these feels uncertain, that’s worth resolving before the next confirmation statement, not after Companies House raises a query.

How does Klea support SIC code accuracy across your entities?

For one company, checking a SIC code is a five-minute task. For a group managing entities across several jurisdictions, it becomes a recurring administrative burden, easy to overlook until a filing gets rejected.

Klea centralises entity data in one place, so your team can see which SIC codes are attached to each entity, when they were last reviewed, and whether they still match current activity. Instead of tracking this across spreadsheets, your team gets one accurate source to check before every confirmation statement.

If SIC code accuracy across your portfolio has become harder to track than it should be, it may be worth reviewing how your entities are currently monitored.

What’s next?

Managing a confirmation statement filing requires detailed planning and full legal awareness. For more insights into processes in other jurisdictions, explore our article: Director ID Reporting: Australia’s 2027 ASIC Rules.

Klea transforms entity management by offering centralised governance, automated compliance, and secure collaboration tools. For this reason, businesses looking for an efficient, scalable solution can take the following actions:

• Request a Demo – See Klea in action for your organisation.
• Start a Trial – Experience first-hand how automation reduces workload and improves efficiency.
• Talk to Our Experts – Get tailored recommendations based on your entity management needs.

Company secretarial software solutions play a crucial role in modern businesses that require structured governance, consistent compliance, and accurate legal entity management. With Klea, organisations can ensure corporate governance remains efficient, transparent, and risk-free.

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