How to Check a Private Investigator Is Legitimate

Updated 13 October 2026 by Investigation Bureau

There is no licence to check in the UK, so you check what would make someone accountable if the work went wrong: the company on the Companies House register, the registration with the Information Commissioner's Office, the named person behind the brand, the written quote and what the firm refuses to do. A legitimate investigator passes those checks in minutes. A risky one fails at least one and talks around it.

Most people searching for this have already found a firm and feel uneasy. This guide sets out the seven checks, the warning signs, the questions for a first call and what a proper report looks like, then runs the checks on us. If you would rather talk it through first, send a confidential enquiry and we reply within one working day.

Why there is no licence to check

Private investigation in the UK is unregulated. The law that licenses door supervisors and security guards also provides for the Security Industry Authority to license private investigators, but that part of it has never been brought into force. There is no licence to apply for, so there is no licence to check. That makes "licensed private investigator" a claim to be wary of rather than reassured by, and a licence for a different activity, such as guarding, does not cover investigation.

Professional bodies exist, but membership is voluntary and a logo proves nothing until the body itself confirms it. The test is accountability. In the UK there is no licence to check, so you check whether there is anyone to hold responsible if it goes wrong.

The seven checks

A registered company on the Companies House register. Ask for the legal name and company number and search the register yourself. The company should be active, with real named directors. A trading name with no company behind it is where the enquiry stops. Our guide to checking whether a company is legitimate shows how to read the record.
Registration with the Information Commissioner's Office as a data controller. Investigation means processing personal data about people who have not consented, so the firm must be registered with the ICO. The register is public: ask for the number and look it up. No registration means the firm is unaware of its duties or ignoring them.
A named person accountable for the work. Someone with a name, a role and a link to the registered company should be responsible for your case. A brand with a contact form and nobody behind it cannot be held to anything.
A fixed written quote before any work starts. Price, scope and what is included, in writing, before you pay. Open-ended hourly billing with no cap means discovering the cost when it is too late to object. Our cost guide shows normal UK rates.
A clear statement of what they will not do. A legitimate investigator has limits and states them without being asked: no phone records, no bank details, no hacking, no blagging. If they are not on the website and not volunteered on the phone, assume there are none.
Evidence prepared so a court can use it, with the method recorded. The end product should be a written report with times, dates, the method and the source of each finding. Photos in a chat thread with no record of how they were obtained are not evidence.
A lawful basis stated for your specific instruction. Every job needs a reason in data-protection terms, and it changes with the case. A trace for a creditor, surveillance for an employer and a check on a partner rest on different grounds, and one may have none. A legitimate firm tells you which applies, and sometimes that the answer is no.

Warning signs

Any one of these should make you pause. Two together should end the conversation.

Guaranteed results. Nobody controls what the evidence turns out to be. A guarantee is a sales line.
Cash only, or payment to a personal account. A company takes payment in its own name. Money to an individual leaves you nobody to claim against.
Offers of phone records, bank details or anything "accessed". These come from deception or hacking, both offences, and you may be liable too. Our guide to what a private investigator can and cannot do draws the line.
No company name on the website. A legitimate firm shows its legal name and number. Silence about it is a choice.
No address for the company on the register. Every registered company has a registered office. If it differs from everything you have been told, ask why.
Pressure to pay today. A genuine investigator can wait a day while you run these checks. Urgency is there to stop you.
A different trading name on the invoice. If the name on the quote, the website and the invoice do not match, you do not know who you are paying.

Questions to ask on the first call

You need five answers, and how they are given tells you as much as the content.

Who will run my case? You want a name, ideally the person you are speaking to. Some firms pass enquiries to whoever will take them.
What is lawful here? Describe what you want and listen for the word "depends". A legitimate investigator says which parts are straightforward, which need a basis and which cannot be done.
What will I receive? A written report you could hand to a solicitor, with the evidence attached and the method recorded.
What happens if nothing is found? Sometimes the honest finding is that nothing is going on. A legitimate firm says so in advance and does not invent a result to justify the fee.
How is my data held, and for how long? Your details and everything gathered about the subject are personal data. The firm should say where it is stored, who sees it and when it is deleted.

What a legitimate report looks like

The report is the product. Everything else is a promise.

A proper report is written, dated and specific. It states what was asked, what was done, when and by whom, and what was found, with each finding tied to its source. Photographs and video are stamped and kept in their original form.

It separates fact from inference. "The subject entered the premises at 14:10 and left at 16:45" is a fact. "The subject is working there" is an inference, and a good report says which is which. It also says what was not found. A report that only ever confirms what the client hoped for is not a report: it is a receipt.

How to check Investigation Bureau

Run the same checks on us. Investigation Bureau is a trading name of Bureau Nine Ltd, on the Companies House register under company number 17484009. We are on the ICO register as a data controller under number ZC259849. The lead investigator responsible for the work is named on our About page. Every instruction starts with a confidential conversation and a fixed quote in writing before any work begins. The hard limits are stated on the site: no phone records, no bank details, no hacking, no blagging and no tracking without a lawful basis.

Frequently asked questions

Do private investigators need a licence in the UK?

No. The law provides for one, but the scheme has never been brought into force, so there is no licence a UK private investigator can hold. Anyone describing themselves as licensed for investigation is mistaken or misleading you. The checks that matter are the public ones: the company record, the ICO registration, a named person and a written quote.

How do I know a private investigator is not a scam?

Run the seven checks before you pay anything and treat the warning signs as a stop list. A scam usually fails the first two outright: no company on the register, or one with no link to the person asking for money, and no ICO registration. If you are still unsure, ask for a day to think and watch how that is received. A legitimate investigator is used to it.

Can I check a private investigator's reviews?

You can, and they help, but they are the least reliable check. Reviews are easy to buy and easy to write yourself. A page of praise with no detail tells you less than one critical review and a considered reply, and a young firm may have few or none. Verify the register entries first: a company record and an ICO registration are public and dated, and a firm cannot write them about itself. Then read the reviews as colour, not as proof.

What should a private investigator never offer to do?

Anything that involves getting information by deception or by breaking into something: phone records, bank statements, medical records, hacking into email, social media or a device, "recovering" someone's messages, and tracking a person or vehicle without a lawful basis. It also covers harassment, trespass and tricking a subject into incriminating themselves. An offer to do any of these is an offer to commit an offence on your behalf, and the evidence is worthless. Walk away.

Check us before you instruct us. The register entries are above and the first conversation is free and confidential. Send a confidential enquiry and we reply within one working day.

Sister service: Trace Bureau is our fixed-price address tracing service, for anyone who only needs a current UK address for a lawful purpose. Charged only when we find them. Investigation Bureau is a Bureau Nine company.