Best Penetration Testing for Ecommerce & Retail
The best penetration testing for UK ecommerce and retail in 2026 comes from CREST-accredited providers that test the full checkout and payment flow for card-skimming and Magecart-style injection paths, cover the web application and the APIs behind headless commerce, understand the commerce platform in scope, and can schedule testing before peak trading season rather than during it. This guide compares 7 providers: Precursor Security, NCC Group, Pen Test Partners, Redscan (Kroll), JUMPSEC, OnSecurity, and WorkNest Secure (formerly Bulletproof).
Seven penetration testing companies compared for UK ecommerce and retail buyers, on the criteria that actually matter for a revenue-critical checkout: card-skimming and Magecart-aware testing, API and headless-commerce coverage, verifiable CREST accreditation, and a schedule that respects your peak trading calendar.
We are Precursor Security, and we have ranked ourselves first on this list.
Rather than pretend otherwise, we publish the selection criteria in full and describe every provider fairly, including where a rival is the better fit. The firms below are genuinely good at what they do; the differences are in checkout and API coverage, transparency, accreditation, and who each serves best for a revenue-critical platform. Confirm any CREST claim in the independent CREST member directory.
Seven firms, side by side
| Provider | CREST status | Pricing published | From |
|---|---|---|---|
| 1. Precursor Security | Pen Test + VA + SOC | Yes | From £2,500 |
| 2. NCC Group | Member firm | No | On application |
| 3. Pen Test Partners | Member firm | No | On application |
| 4. Redscan (Kroll) | Member firm | No | On application |
| 5. JUMPSEC | Member firm + NCSC CHECK | No | On application |
| 6. OnSecurity | Member firm | No | Instant quote via platform |
| 7. WorkNest Secure (formerly Bulletproof) | Member firm | No | On application |
Verified against each provider's public website, September 2026. "No" under pricing means a rate was not published at the time of writing, not that a provider is more expensive. Redscan is part of Kroll (US-headquartered). Bulletproof and Pentest People were consolidated under the WorkNest Secure brand in May 2026.
The 7 best for UK ecommerce
& retail in 2026
1. Precursor Security
Precursor holds triple CREST accreditation across Penetration Testing, Vulnerability Assessment, and Security Operations Centre. Testing covers the checkout and payment flow end to end: card-skimming and Magecart-style injection paths, third-party script exposure, session and authentication handling, plus the REST and GraphQL APIs behind headless commerce and mobile shopping apps. We can also provide ASV scanning for the quarterly external vulnerability scan PCI DSS Requirement 11.3 demands, alongside the Requirement 11.4 penetration test. Every tester is a UK-based, DBS-checked employee. Testing starts from £2,500 at approximately £1,200 per consultant day, published on the website, with a retest included in every engagement and a written quote within 24 hours. We work around your trading calendar, scoping and delivering testing well ahead of Black Friday and the holiday peak rather than during it, and findings feed detection rules through the closed-loop model so assurance continues between annual tests.
Trade-off: A UK mid-market specialist rather than a global enterprise brand, and Precursor provides the penetration testing and ASV scanning, not a QSA-led PCI DSS Report on Compliance.
2. NCC Group
NCC Group is one of the largest security consultancies in the world, headquartered in Manchester, with the bench depth to staff large, multi-region testing programmes across a retailer's web, mobile, and API estate. For an enterprise retailer running a global platform that needs a coordinated testing programme scheduled around Black Friday and holiday trading, few firms match its capacity.
Trade-off: Engagement model and pricing are built for enterprise procurement. Costs are on application.
3. Pen Test Partners
Pen Test Partners are the UK's best-known specialists in embedded and operational technology, with a long track record researching payment terminals, ATMs, and point-of-sale hardware. For an omnichannel retailer whose risk extends beyond the online checkout into in-store card terminals, self-checkout kiosks, or click-and-collect hardware, their heritage in payment hardware is the differentiator.
Trade-off: A specialist hardware and embedded-systems focus; standard ecommerce web and API testing is not their distinctive strength. Pricing on application.
4. Redscan (Kroll)
Redscan, now part of Kroll, pairs a large penetration testing practitioner organisation with Kroll's global incident response and forensics business. For a retailer that wants its checkout testing, its Magecart incident retainer, and its post-breach forensics under one enterprise supplier, the Kroll relationship is the draw.
Trade-off: Kroll is US-headquartered, and the engagement model leans enterprise. Pricing on application.
5. JUMPSEC
JUMPSEC holds NCSC CHECK status alongside CREST membership, with a strong red teaming and adversary-simulation practice useful for testing fraud controls and account-takeover defences under realistic attack conditions. For a retailer with PSN-connected or government-adjacent systems that mandate CHECK delivery, that combination is the differentiator.
Trade-off: Pricing on application.
6. OnSecurity
OnSecurity runs a platform-first, pentest-as-a-service model with instant online quoting and quick scheduling. For a growing ecommerce merchant that needs a checkout or API test booked this week ahead of Black Friday, a funding round, or a payment-partner review, the platform model works well.
Trade-off: Quotes are generated through the platform rather than published as a rate card, and the model suits smaller, repeatable scopes rather than a full omnichannel programme.
7. WorkNest Secure (formerly Bulletproof)
Bulletproof and Pentest People were brought together under the WorkNest Secure brand in May 2026, combining penetration testing with a broad compliance practice covering PCI DSS, Cyber Essentials, and ISO 27001. For a smaller ecommerce merchant that wants checkout testing and PCI compliance evidence handled by a single supplier, that combined offering suits.
Trade-off: A newly consolidated brand following the Bulletproof and Pentest People merger, and a generalist compliance breadth play rather than an ecommerce testing specialist. Pricing on application.
How we ranked them for ecommerce
Six criteria that matter specifically to a retailer or ecommerce merchant buying penetration testing for a revenue-critical platform, each something you can verify without taking anyone's word for it. Weighting is ours; the facts are checkable.
Whether the provider tests the checkout itself for card-skimming and Magecart-style script injection paths, not just the surrounding network. This is the work that maps to PCI DSS Requirement 11.4 and matters most on a revenue-critical page.
Whether testing extends to the REST or GraphQL APIs behind mobile apps and headless commerce, not only the public-facing storefront. Modern ecommerce architectures move most of the attack surface into the API layer.
Whether the provider has genuine experience with your commerce platform, whether that is Shopify, Magento, WooCommerce, a headless build, or a custom stack, rather than treating every ecommerce engagement identically.
Whether the provider will scope and deliver testing well ahead of Black Friday and the holiday trading period, so remediation and a retest complete before load peaks, not during it.
Company and individual CREST accreditation, checkable in the public directory. It is the accreditation most UK acquirers, insurers, and auditors look for on a penetration testing supplier.
Whether findings feed ongoing detection rather than sitting in a PDF until next year's peak season. A platform under continuous fraud and skimming pressure benefits from the closed-loop model.
Red flags for an
ecommerce buyer
Whichever firm you choose, including us, walk away if you see these.
A vulnerability scan sold as a pentest on your checkout
Engagements priced under £500 a day are automated scans with a human cover sheet. Ask how many days of manual testing target the checkout and payment flow specifically, not just the surrounding infrastructure.
Testing scheduled into peak trading
A provider that offers you a slot the week of Black Friday, rather than well before it, has not thought about your business. Remediation and a retest need to land before load peaks, not during it.
No payment-flow or PCI segmentation scope
If the scope does not name the checkout, the cardholder data environment, or segmentation testing explicitly, do not assume it is covered. Ask for it in writing before you sign.
Frontend-only testing that ignores the API
A test that only exercises the storefront and skips the REST or GraphQL APIs behind your mobile app and headless commerce misses where most modern ecommerce attack surface lives.
No retest before your PCI deadline
A test without verification of your fixes is half a service. If the retest is a separate paid engagement, your remediation evidence for the PCI deadline or acquirer review costs double and may not land in time.
Opaque pricing with no day rate on offer
A firm that cannot indicate a day rate before a discovery call adds procurement drag when you are working to a replatform go-live or a trading-season deadline. UK CREST day rates run £1,000 to £1,500.
Ecommerce penetration testing prices
CREST-accredited testing runs £1,000 to £1,500 per consultant day. At Precursor's published rate of approximately £1,200 per day: external network from £2,500, web application (including checkout and payment flow) from £3,750, internal network from £6,250, and full multi-scope assessments covering web, mobile, and API from £10,000. ASV scanning for the quarterly PCI DSS scan is quoted alongside your annual testing.
Full cost guide with worked examplesMore on securing an ecommerce or retail platform and the services referenced above.
Compare us against anyone on this list.
UK-based, DBS-checked testers. Fixed pricing published before you call. A written quote within 24 hours of scoping. Retest included.
Penetration testing for ecommerce
The questions retailers and ecommerce merchants ask most when comparing UK providers.
UK ecommerce penetration testing runs from £2,500 for a small external network test to £3,750 or more for a full web application and checkout assessment, at roughly £1,000 to £1,500 per consultant day from a CREST-accredited provider. A comprehensive scope covering the web platform, mobile apps, and APIs behind headless commerce typically reaches £10,000 to £15,000. Most firms price on application; Precursor publishes its rates, starting from £2,500. Full pricing by scope is set out on our penetration testing cost guide.
Yes, if you store, process, or transmit cardholder data, or your checkout touches the cardholder data environment even via a hosted payment page. PCI DSS Requirement 11.4 requires external and internal penetration testing of that environment at least annually and after any significant change, such as a replatform or new payment integration. Requirement 11.3 separately requires quarterly external vulnerability scanning by an Approved Scanning Vendor (ASV), which is a scan, not a penetration test. Most merchants need both, and the two are not interchangeable.
Well ahead of your peak trading period, not during it. Book testing 6 to 8 weeks before Black Friday, Cyber Monday, or the holiday season so remediation and a retest complete before traffic peaks, not while your checkout is under live load. The other common trigger is after significant change: a platform migration to Shopify, Magento, WooCommerce, or a headless commerce architecture, a new payment integration, or a major feature release should each be followed by testing before go-live.
A proper ecommerce penetration test covers the checkout and payment flow (card-skimming and Magecart-style injection paths, third-party script exposure, session handling), customer authentication and account takeover resistance, the REST or GraphQL APIs behind mobile apps and headless commerce, and the admin or back-office platform attackers target to reach customer and order data. A scope that only tests the public-facing frontend and ignores the API layer and admin console leaves the parts of the platform most likely to hold customer data untested.
UK retailers and ecommerce merchants commonly shortlist a mix of specialists and larger consultancies. This guide compares seven: Precursor Security, NCC Group, Pen Test Partners, Redscan (Kroll), JUMPSEC, OnSecurity, and WorkNest Secure (formerly Bulletproof). The right choice depends on whether the firm tests the full checkout and API surface, whether pricing is published, whether a retest is included for your remediation evidence, and whether testing can be scheduled around your trading calendar. Confirm any CREST accreditation in the public directory at crest-approved.org.