The Best Penetration Testing Companies for UK Law Firms (2026)

The best penetration testing companies for UK law firms in 2026 are listed below. Each one holds a verified CREST penetration testing accreditation and shows public evidence of working with the legal sector, and each is compared on published pricing, retests and report turnaround.

1. Mitigo

Mitigo is a UK cyber risk management company that names law firms and chambers among the sectors it specialises in, and it is the cyber security provider listed in the Law Society’s member offers, where it is described as providing cybersecurity and cyber risk management services to the legal sector. It is CREST-accredited for penetration testing. Verified: CREST Marketplace listing.

2. EJN Labs

EJN Labs is a CREST-accredited UK penetration testing consultancy with a dedicated law firm penetration testing service covering document management systems and client portals. It is one of three companies on this list that publish pricing. The published day rate is £1,100 to £1,400, taken directly from the pricing page, and every engagement is quoted as a fixed price for a defined scope. The business holds ISO 27001, ISO 9001 and Cyber Essentials Plus. Verified: CREST Marketplace listing for EJN Labs.

For a law firm, what the fixed price includes matters as much as the number. Retesting of fixed findings is free until the issues are resolved, so the evidence that your fixes worked, which is what a client security questionnaire or an insurer asks for, is part of the original quote. Findings are delivered live to a client portal as they are confirmed, so your IT team or managed provider can start fixing on day one. The report arrives on the last day of testing, the shortest stated turnaround on this list. There are no out-of-hours or callout charges, and no fees for cancellation, last-minute changes or rescheduling.

Testing is delivered by UK-based, CREST-certified penetration testers, which matters when the systems in scope hold privileged material. Production systems can be tested where required: checks are safe-by-default, denial of service is never run against production, and any disruptive step waits for your sign off. Out of hours or overnight slots are available so fee earners are not interrupted. Reports give each finding a CVSS score and prioritised remediation guidance, followed by a walkthrough call, and are written to be handed to a client’s security team, an insurer or an auditor.

Mitigo’s standing with the Law Society keeps it first. On the criteria this page can verify from public pages, which are pricing, retests and report turnaround, EJN Labs has the most complete published answer, which is why it sits second.

3. Precursor Security

Precursor Security is a UK offensive security consultancy with a published legal sector service for law firms, barristers’ chambers and legal technology companies. It also publishes pricing: its cost page states engagements from £2,500 at approximately £1,200 per consultant day, with a 30-day retest, and its penetration testing page states a report within 5 working days of test completion. CREST-accredited for penetration testing, vulnerability assessment and security operations centre. Verified: CREST Marketplace listing.

4. Kroll (incorporating Redscan)

Kroll is a global risk advisory firm whose UK cyber practice absorbed Redscan. Redscan’s cyber security services for law firms page describes its experience of working with organisations across the legal sector. Kroll holds CREST accreditation for penetration testing, incident response and security operations centre. Redscan has no standalone listing, so check the Kroll entry. Verified: CREST Marketplace listing for Kroll LLC.

5. Sentrium

Sentrium is an independent UK penetration testing consultancy with a dedicated legal sector page focused on risk and compliance. Its penetration testing page states that a free retest is included. Its service pages give indicative price ranges by test type. CREST-accredited for penetration testing. Verified: CREST Marketplace listing.

6. Sencode

Sencode is a UK penetration testing company with a legal services page covering applications, networks, cloud platforms and access controls for law firms. That page states a complimentary retest and a report typically within 5 days of testing. CREST-accredited for penetration testing. Verified: CREST Marketplace listing.

7. ProCheckUp

ProCheckUp is a long-established UK security consultancy whose CREST listing shows 17 years of membership and names international law firms among its clients. Its accreditations span penetration testing, vulnerability assessment, incident response and threat led penetration testing. Verified: CREST Marketplace listing.

8. Evalian

Evalian is a UK data protection and security consultancy whose CREST listing names legal services among the sectors it works in, a useful pairing for firms that want testing and UK GDPR advice from one supplier. Its penetration testing page states a free retest and a report within seven days of completing the test. CREST-accredited for penetration testing, vulnerability assessment, incident response and security operations centre. Verified: CREST Marketplace listing.

9. Fortifi Cyber

Fortifi Cyber is a UK penetration testing company that appears as a sponsor of the British Legal Technology Forum, a legal technology event. CREST-accredited for penetration testing. Verified: CREST Marketplace listing.

How we selected these companies

Every company on this list passed the same two entry checks: a live listing in the CREST Marketplace supplier directory confirming penetration testing accreditation, and public evidence of work with the legal sector. We then recorded what each company publishes about pricing, retests and report turnaround. All pages were checked on 7 October 2026.

• CREST accreditation, verified. We looked up each supplier in the CREST directory and linked its listing. No listing, no entry: brands absorbed into a parent company appear under the parent.
• Legal sector evidence. A general penetration testing company was not enough. Each entry needed a public page showing legal sector work: a dedicated legal sector service page, a professional body listing, a legal sector event, or law firms named among its clients on its CREST listing. Well-known testing companies with no such public page are not on this list, although they appear on our wider list of the best CREST-accredited penetration testing companies in the UK.
• Published pricing. We recorded whether a company publishes its own prices on a public page. General statements about what the market charges were not counted as a company’s own pricing.
• Retests and report turnaround. A law firm usually has to prove that findings were fixed, and often by a client’s deadline. Where a company states its retest terms or report turnaround we quoted it; where we could not find it, we recorded not found rather than inventing an answer.

How the companies compare

All nine companies hold verified CREST penetration testing accreditation, show a United Kingdom headquarters on their listing except Kroll, and have public legal sector evidence. The practical differences are in what they publish.

Accreditation is taken from each company’s CREST Marketplace listing. Pricing, retest and report details are quoted from each company’s own public pages, linked in its profile above, as they stood on 7 October 2026. Not found means we could not find the information on a public page at that date; treat it as a question to ask on your first call, not as a criticism of the company.

Do law firms have to have a penetration test?

No rule names a penetration test as mandatory for a law firm in England and Wales. The duties that lead firms to commission one are broader. Paragraph 2.1 of the SRA Code of Conduct for Firms requires effective governance structures, arrangements, systems and controls, and paragraph 2.5 requires a firm to identify, monitor and manage all material risks to its business. Paragraph 6.3 of the SRA Code of Conduct for Solicitors requires the affairs of current and former clients to be kept confidential.

UK GDPR Article 32 adds a duty to implement appropriate security measures, including, as appropriate, a process for regularly testing, assessing and evaluating their effectiveness. A penetration test is one recognised way to evidence that process. When the SRA visited 40 firms for its cyber security thematic review, published on 2 September 2020, 30 reported having been the target of a cyberattack and 19 had undergone penetration testing by an external party. The NCSC’s Cyber Threat Report: UK Legal Sector sets out why the sector is targeted.

In practice the request usually comes from outside the firm: a corporate client’s security questionnaire, a panel review or a cyber insurer. Firms working towards LOCS:23, the ICO-approved UK GDPR certification scheme for legal services, should note that it requires an external and an internal vulnerability scan at least once a year (controls 8.3.7.14 and 8.3.7.15) and lists penetration testing among the protective measures a certified firm evidences (control 8.3.7.13). For scope and cost, see our guide to penetration testing for law firms.

What a law firm should ask a penetration testing company

1. Which legal entity holds your CREST accreditation? Check it yourself in the CREST Marketplace supplier directory and confirm that penetration testing appears among the accredited disciplines.
2. Where are the testers based, and who will see our data? Matter files and privileged correspondence may be visible during testing, so ask where the people doing the work are located and how findings are stored.
3. Is a retest included, and for how long? Clients and insurers ask for evidence that findings were fixed, so a retest that is capped or charged separately changes the real price.
4. When do we get the report? If a client deadline or renewal date is driving the test, the gap between the end of testing and the report matters.
5. Can you test without interrupting fee earners? Ask about out of hours testing and how disruptive checks are handled on live systems.
6. What is the fixed price for our scope? Ask for a day count and a day rate, not a range.

Get a quote

Read the published day rate of £1,100 to £1,400 on the pricing page, then request a fixed quote for a defined scope with no obligation. Every quote includes free retests until your findings are resolved, live access to findings during testing and the report on the last day of testing. Get a penetration testing quote, or read more about penetration testing for UK law firms.

Related: Penetration Testing Cost for UK Law Firms.