How to Check if a UK Company Is Legitimate — 10 Checks That Cost Almost Nothing

Updated 1 August 2026 by K3K Investigations

Fake companies are cheap to build and expensive to believe. A convincing UK company can be assembled in an afternoon — a £12 incorporation, a virtual office in a good postcode, a templated website and a bought review profile. The checks that expose one cost almost nothing and take under an hour. Here are the ten we run first, and the signs that tell an investigator a company is dressed up rather than real.

This guide is written for both sides of our casework: businesses about to extend credit or pay a large deposit, and individuals about to hand money to a firm they found online. The checks are the same; only the stakes differ.

The ten checks

Find them on Companies House — then read, don't skim. Free. Confirm the exact legal name and company number match what is on their website and invoices. A trading name with no registered company behind it, or a name one letter off a well-known firm, is your answer already.
Check the incorporation date against the story. "Twenty years of experience" attached to a company registered eight months ago needs explaining. Sometimes the explanation is legitimate — a rebrand or restructure — but it is theirs to give.
Read the officers' history. Click through each director: what else do they run, and what happened to it? A chain of dissolved companies in the same line of business — phoenixing — is the single strongest red flag on this list.
Check the filings are current. Overdue accounts, overdue confirmation statements, or an active proposal to strike off — all free to see, all routinely ignored by victims until afterwards.
Test the registered address. Search it: if it is a virtual-office provider serving thousands of companies, that is normal for a startup but inconsistent with claims of showrooms, warehouses or "our London headquarters". Street View is your friend.
Verify the VAT number on the government's VAT-checker if they charge VAT. An invalid or missing number on invoices that charge it is not sloppiness; it is a fact you can act on.
Check CCJs. TrustOnline (Registry Trust) reports county court judgments against companies and individuals for a few pounds. Money judgments against a firm asking you for money upfront changes the conversation.
Age the website. A whois lookup shows when the domain was registered. A "long-established" firm on a domain registered three months ago, stock photography, and no named humans is a pattern, not a coincidence.
Check the regulated register if the trade has one. Financial services on the FCA register, letting agents in a redress scheme, gas engineers on Gas Safe. Claiming a regulated trade without the registration is decisive.
Call the landline, not the mobile. A real business address answers, or at least rings, on a geographic number. A company reachable only through a mobile and a webform, whose address turns out to be a letterbox, has failed a test it did not know it was sitting.

The red flags behind the checks

The individual checks matter less than the pattern. What an investigator is really reading for: pressure (discounts that expire today, deposits demanded by bank transfer), asymmetry (they know everything about you, you can verify nothing about them), and borrowed credibility (awards you cannot verify, reviews that cluster in one fortnight, a prestige address that turns out to be rented by the hour).

Payment method is its own tell. Card payments carry chargeback rights; bank transfers do not. A company steering you away from card payment toward "direct transfer to secure your order" is moving risk from itself to you.

When the checks fail — or the stakes are too high for a checklist

If the checks above come back wrong, walk away; you do not owe anyone a second chance at your money. If they come back clean but the amount at stake is significant — a large contract, trade credit, a supplier who will hold your deposit for months — clean public records are necessary but not sufficient. That is where professional company evaluation starts: ownership behind the ownership, the substance at the address, the litigation record, the principals' real history, done before the money moves rather than after.

And if the money has already gone, act quickly: report to Action Fraud, notify your bank in writing, preserve every message — and if the sums justify it, our fraud investigation team traces where it went and builds the evidence for recovery.

Frequently asked questions

Can a company be on Companies House and still be a scam?

Easily — incorporation is registration, not vetting. Companies House checks identity documents at formation, not honesty. Treat presence on the register as the beginning of verification: it gives you the officers, dates and filings to test the story against.

What is the fastest single check?

The director history. Legitimate businesspeople occasionally have a failure behind them; serial formation-and-dissolution in the same trade is the pattern that pays to spot, and it takes five minutes of clicking through officer records.

How do I verify an overseas company?

The same logic, different registers — most jurisdictions have a companies register, but quality and openness vary enormously, which is precisely why overseas counterparties are where professional due diligence earns its fee. See our guide to due diligence on a business partner.

When is it worth paying an investigator instead?

When the exposure is large, the counterparty is overseas, or something in your own checks will not reconcile and you need to know why before committing. A fixed-price evaluation costs a small fraction of the deposit, credit line or contract it protects — and if a scoping call shows the public record already answers you, we say so for free: 020 3343 7007.

About to pay a company you cannot quite verify? Run the ten checks — and if the stakes are high or the answers do not reconcile, speak to a senior investigator in confidence before the money moves. Call 020 3343 7007 (24 hours) or book a call.