Companies House red flags: 12 warning signs on the register

Which red flags matter most?

The red flags that matter most are the ones Companies House itself has acted on: a default registered office, a strike-off proposal and overdue filings. Signs that depend on the company's own choices, such as frequent address or director changes, matter when they cluster.

Use the list in two ways. Any one flag is a reason to ask a question. Two or more together, especially from the first five, are a reason to ask for payment up front or to stop before you sign. Our general routine is in how to check a UK company; this page goes deeper on each warning sign.

Key facts:

• Since 4 March 2024, every company must have an "appropriate address" as its registered office and cannot use a PO Box (GOV.UK).
• If Companies House moves a company to its default address, the company has 28 days to supply a new appropriate address, or the registrar may start striking it off (GOV.UK).
• A legal entity can only be recorded as a PSC if it is subject to its own disclosure requirements, such as a UK company or one listed on certain regulated markets (GOV.UK).
• On 1 October 2026, 27,748 companies were registered at the default address and 83% of them were under a strike-off proposal (UK Company Data, strike-off study).

The 12 red flags at a glance

All 12 flags can be checked for free on the public register in about ten minutes.

Strength is our editorial judgement of how often the flag points to a real problem, not a score.

1. Registered office at the default address

A registered office at PO Box 4385, Cardiff CF14 8LH is the strongest single warning sign on the register. Companies House moves a company there when it finds that the registered office is not an appropriate address, for example because the company has no right to use it.

The company then has 28 days to deliver a new appropriate address with evidence that it can use it. If it does not, the registrar may begin striking it off. In our data, 22,977 of the 27,748 companies at that postcode (83%) were already under a strike-off proposal on 1 October 2026.

2. A strike-off proposal

"Active - Proposal to Strike off" means a first Gazette notice has been published and the company can be dissolved not less than two months later. It covers both compulsory strike-off and directors' own applications to close.

On 1 October 2026, 423,006 companies carried this status, 7.6% of active and proposed companies, and 58% of them were also overdue with their accounts. If such a company owes you money, see how to object to a company strike-off before the dissolution date.

3. Overdue accounts

Overdue accounts are a strong signal when they are months late or late year after year, and a weak one when they are a few weeks late. On 1 October 2026, 93,785 active companies (1.8%) were overdue, 74% by less than three months, and 8,175 by more than two years (overdue accounts study).

Our guide to what "accounts overdue" means explains the penalties and how to read different lengths of delay.

4. Overdue confirmation statement

An overdue confirmation statement is a strong flag because the filing is short and cheap: missing it usually means nobody is looking after the company. Not filing is an offence, and Companies House can fine the company or strike it off.

Since the identity verification rules began on 18 November 2025, a company also cannot file its statement until all its directors have verified their identity. See confirmation statement overdue for the detail.

5. Frequent registered office changes

Several registered office changes in a year can mean a company is avoiding correspondence, creditors or enforcement. There are innocent explanations, such as a move to an accountant's address or a new office, so count the changes over two years and compare them with the company's age and size.

6. Recent incorporation with large contracts or claims

A company incorporated in the last few months has no accounts and no filing record, so you are trusting the people, not the company. That is normal for a start-up selling small orders. It is a flag when the company asks for a large deposit, claims a long trading history or bids for a contract far beyond what a new business could deliver.

New companies are common: 715,974 live companies were incorporated in 2025 and 592,744 in 2026 to 1 October. Check whether the directors ran a similar business before, and what happened to it.

7. Frequent or wholesale director changes

Director churn matters when it is frequent or total. Several appointments and resignations in a year, or every director replaced on the same day, can mean a change of control, a dispute or a company passed to a nominee.

Also check the directors themselves. Open each director's other appointments: a person with dozens of current appointments, or a history of companies dissolved after strike-off, deserves a question.

8. Overseas or untraceable ownership chain

The PSC tab shows who owns or controls the company, and a flag arises when you cannot follow the chain to a real person. As a rule, a legal entity can only be recorded as a PSC if it is subject to its own disclosure requirements, for example a UK company with its own PSC register or a company listed on certain regulated markets. Otherwise the company should look through it to the individual behind it.

So a PSC that is a private company registered abroad, a chain of several holding companies, or a statement that no registrable person can be identified, all mean you cannot see the ultimate owner from the UK register. That is legal in some structures, but you should ask who owns the business before extending credit.

9. Dormant accounts while trading

Dormant accounts state that the company had no significant accounting transactions in the year. If the same company was sending invoices, running a website with sales or employing staff in that year, the accounts and the business do not match.

On 1 October 2026, 559,853 active companies (10.8%) had last filed dormant accounts. Most are genuine, such as unused group companies or name-holders. The flag is the mismatch, not dormancy itself; see dormant company.

10. Net liabilities growing every year

A balance sheet with net liabilities that grow every year shows losses being funded by somebody. Negative net assets alone do not mean insolvency, and director-funded companies often show them for years.

What makes it a flag is the direction combined with short-term pressure: net current liabilities, rising amounts owed to HMRC or trade creditors, and late filing. Our guide to negative net assets explains the legal tests and what to check next.

11. Accounting reference date moved repeatedly

Moving the year end, and especially extending the accounting period, pushes back the date the next accounts are due. Doing it once for a group restructure is normal; doing it repeatedly can be a way to delay publishing bad numbers.

Look in the filing history for "change of accounting reference date" entries and compare them with when accounts actually arrived. See accounting reference date for how the deadline is set.

12. Recent name change or a lookalike name

A company that changed its name recently, or has a name one word away from a well-known business, can be used to borrow someone else's reputation. The company overview lists previous names with dates.

Search the register for the well-known name as well. If the invoice quotes a name that matches a larger, older company but the number belongs to a newer one, treat it as possible impersonation and follow the steps in check a supplier before paying.

What the register cannot confirm

Companies House is not a guarantee of honesty. Since 4 March 2024 it has stronger powers to query information and remove inaccurate information, but the figures in accounts are still the company's own, and the register does not show county court judgments or payment behaviour. For those, see our free credit check guide. To see most of the flags above for a company in one view, search it on our accounts page.

Sources

1. Set up a private limited company: rules for registered office addresses and email addresses, GOV.UK, accessed 17 October 2026.
2. Companies House begins phased roll out of new powers to tackle fraud, GOV.UK, accessed 17 October 2026.
3. Striking off or dissolving a limited company, GOV.UK, accessed 17 October 2026.
4. People with significant control (PSCs), GOV.UK, accessed 17 October 2026.
5. Confirmation statement guidance, GOV.UK, accessed 17 October 2026.
6. Companies House confirms identity verification rollout from 18 November 2025, GOV.UK, accessed 17 October 2026.

FAQ

What does PO Box 4385 Cardiff CF14 8LH mean on a company record?

It is the Companies House default address. Companies House moves a company's registered office there when the company has no right to use the address it gave. The company then has 28 days to supply a new appropriate address with evidence, or the registrar may start striking it off. On 1 October 2026, 83% of companies at that address were under a strike-off proposal.

What are the biggest red flags when checking a UK company?

The strongest are the ones Companies House has acted on: a registered office moved to the default address, a strike-off proposal and long-overdue accounts or confirmation statement. Dormant accounts while the company is clearly trading are also serious. Frequent address or director changes, untraceable ownership and growing net liabilities matter most when two or more appear together.

Is a company with many director changes a risk?

Not always, but it deserves a question. Frequent appointments and resignations, or every director replaced on the same day, can mean a change of ownership, a dispute or a company handed to a nominee. Open each director's other appointments too: a history of companies struck off or dissolved shortly after they joined is a stronger warning than the changes themselves.

Why would a company's PSC be another company overseas?

Usually because the business is owned through a holding structure. As a rule, a legal entity can only be recorded as a PSC if it is subject to its own disclosure requirements, such as a UK company or one listed on certain regulated markets; otherwise the company should look through it to the individual. An overseas private company as PSC means you cannot see the real owner from the UK register.

Sources: Companies House register and accounts data (Open Government Licence v3.0), legislation.gov.uk and GOV.UK guidance where linked. This page is general information, not legal, tax or credit advice. Spotted an error? Email info@globalmindsetmarketing.co.uk.