The Best Cloud Penetration Testing Companies UK
The best UK cloud penetration testing companies in 2026 test AWS, Azure, GCP, and Microsoft 365 by actively exploiting IAM and identity misconfigurations rather than just reviewing configuration. This guide compares 7 leading providers: Precursor Security, NCC Group, Pen Test Partners, Redscan (Kroll), JUMPSEC, OnSecurity, and LRQA, on criteria any buyer can check independently.
Seven CREST-accredited UK cloud penetration testing companies compared on the criteria that matter for AWS, Azure, GCP, and Microsoft 365: verifiable accreditation, identity and IAM exploitation depth, multi-cloud coverage, and pricing you can see before a sales call.
We are Precursor Security, and we have ranked ourselves first on this list.
Rather than pretend otherwise, we publish the selection criteria in full, describe every competitor fairly, and link the independent CREST member directory so you can check our working. The firms below are genuinely capable of testing cloud environments. The differences are in platform depth, delivery model, and who each firm serves best.
Seven firms, side by side
| Provider | CREST status | Pricing published | From |
|---|---|---|---|
| 1. Precursor Security | Pen Test + VA + SOC | Yes | From £3,750 |
| 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. LRQA | Member firm + NCSC CHECK | No | On application |
Verified against each company's public website, September 2026. "Not published" means we could not find the price publicly stated; it does not mean the firm lacks a rate card.
The 7 best UK cloud penetration
testing companies in 2026
1. Precursor Security
Precursor tests AWS, Azure, GCP, and Microsoft 365 under the same CREST-accredited methodology, with a dedicated deep-dive page and published pricing for each platform. A single-account or single-tenant assessment starts from £3,750, and a multi-cloud engagement spanning two or more providers starts from £8,000. Every engagement runs on a read-only access model (ReadOnlyAccess and SecurityAudit on AWS, Reader and Security Reader on Azure, Viewer and Security Reviewer on GCP), actively exploits IAM and Entra ID misconfigurations rather than just flagging them, and feeds findings directly into SOC detection rules for clients who also use our monitoring services.
Trade-off: A mid-market specialist rather than a global enterprise brand, and the youngest firm on this list.
2. NCC Group
NCC Group is one of the largest security consultancies in the world, headquartered in Manchester, with the bench depth to staff very large, multi-region, multi-cloud assessment programmes. For a FTSE-100 estate spanning several cloud providers and geographies, few firms can match the capacity.
Trade-off: Engagement model and pricing are built for enterprise procurement. Costs are on application.
3. Pen Test Partners
Pen Test Partners built their reputation on embedded and operational technology: connected vehicles, ships, planes, and industrial control systems. That expertise increasingly overlaps with cloud, since most of those devices report telemetry into an AWS or Azure backend. If your risk lives partly in hardware and partly in the cloud services behind it, they cover both ends.
Trade-off: Cloud testing is an extension of their hardware specialism rather than their primary focus. Pricing on application.
4. Redscan (Kroll)
Redscan, now part of Kroll, pairs a large practitioner organisation with the backing of a global incident response and forensics business. If a cloud compromise ever happens, there is value in the firm that tested your AWS or Azure estate also leading the forensics response, under one contract.
Trade-off: Pricing on application, and the engagement model leans enterprise.
5. JUMPSEC
JUMPSEC holds NCSC CHECK status alongside CREST membership, which makes them a strong choice for PSN-connected environments and government cloud migrations that mandate CHECK delivery over general CREST accreditation.
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 startup that needs a single AWS account or a small SaaS cloud footprint tested this week with minimal procurement friction, the platform model works well.
Trade-off: Quotes are generated through their platform rather than published as a rate card, and the model favours smaller, single-cloud scopes over complex multi-cloud estates.
7. LRQA
LRQA (formerly Lloyd's Register Quality Assurance) runs CREST-certified cloud penetration testing across AWS, Azure, and GCP, backed by cloud-platform-certified consultants and a global assurance business operating in more than 55 countries. For an organisation that wants its cloud pentest, ISO 27001 certification, and PCI DSS assessment under one supplier, the breadth is the draw.
Trade-off: An assurance and certification body first, testing specialist second. Pricing on application.
Explore cloud testing by platform
Cloud Testing Hub
AWS, Azure, GCP, and Microsoft 365 in one overview.
AWS Penetration Testing
IAM, S3, Lambda, and EKS exploitation.
Azure Penetration Testing
Entra ID, Conditional Access, and AKS.
Microsoft 365 Assessment
Conditional Access, Exchange, SharePoint, Teams.
How we ranked them
Six criteria specific to cloud testing, each something a buyer should verify before signing a scoping call. Weighting is ours; the underlying facts are checkable.
Most cloud breaches trace back to misconfiguration and identity abuse, not unpatched CVEs. A firm that only flags settings against a benchmark has not proven anything is exploitable; the good ones chain findings into a real attack path.
Entra ID Conditional Access bypass, IAM role chaining, service account impersonation: identity is the primary cloud attack surface. A cloud pentest without deep identity testing is missing the part that matters most.
AWS, Azure, GCP, and Microsoft 365 each have a different identity model and attack surface. A provider that only tests one platform well cannot give a multi-cloud estate a consolidated risk view.
AWS, Azure, and GCP no longer require pre-approval for testing your own resources, but scope discipline against each provider's acceptable use policy still matters. A firm that gets this wrong puts your account standing at risk.
Company accreditation in the CREST directory, and individual tester certification, not just an organisational badge or a cloud vendor certification alone.
A cloud pentest report that gathers dust delivers half the value. The strongest engagements feed exact findings into ongoing cloud monitoring, closing the loop between offensive and defensive security. Read more about our closed-loop security model.
Red flags when choosing
a cloud pentest company
Whichever firm you choose, including us, walk away if you see these.
A CSPM report sold as a cloud pentest
Automated tools like Prowler, ScoutSuite, or a vendor CSPM dashboard produce a configuration report, not a penetration test. If the deliverable looks like a list of benchmark deviations with no proof-of-concept exploitation, you have paid pentest prices for a scan.
Config-only review with no exploitation of the paths found
Flagging that an IAM role has iam:PassRole is the easy part. A real test chains that permission with an accessible Lambda function or an overly permissive bucket policy to demonstrate the actual escalation path to administrator access.
No identity or Conditional Access coverage
Entra ID misconfigurations and IAM privilege escalation are the leading cause of cloud compromise. A cloud pentest that skips Conditional Access bypass testing and identity attack paths has skipped the part attackers care about most.
Single-cloud shops for a multi-cloud estate
AWS IAM, Azure RBAC, and GCP's binding model are structurally different. A tester fluent only in AWS will miss GCP-specific service account impersonation chains, and vice versa.
No retest included
A cloud pentest without verification of your fixes is half a service, particularly when the report is being used as evidence for an ISO 27001 or SOC 2 audit.
Opaque pricing
Cloud engagements should be quoted on a fixed basis after a scoping call defines the accounts, subscriptions, or tenants in scope. If a firm cannot give you a price range before a sales call, comparison shopping becomes impossible.
UK cloud penetration testing prices in 2026
At Precursor's published rates: a single AWS account, Azure subscription, GCP project, or Microsoft 365 tenant starts from £3,750 for a 3 to 5 day engagement. A multi-cloud environment spanning two or more providers starts from £8,000 for an 8 to 10 day engagement. Most firms on this list price on application.
Full cost guide with worked examplesCompare us against anyone on this list.
Fixed pricing across AWS, Azure, GCP, and Microsoft 365, published before you call. A written quote within 24 hours of a scoping conversation.
Choosing a cloud pentest company
The questions buyers ask most when comparing UK cloud security providers.
A single-account or single-tenant cloud penetration test (AWS, Azure, GCP, or Microsoft 365) starts from £3,750 for a 3 to 5 day engagement. Larger environments spanning two or more cloud providers, or a single provider with multiple accounts and Kubernetes or serverless architecture, typically start from £8,000 and can run to £15,000 or more. Precursor publishes fixed pricing after a free scoping call; most other firms on this list quote on application.
Generally, no. AWS removed the requirement for prior approval on customer-side testing in 2019, and Azure and GCP operate under similar policies: no pre-approval is required to test resources you own. What still matters is scope discipline. You need explicit written authorisation from the resource owner, the test must stay within the accounts, subscriptions, or projects agreed at scoping, and prohibited activities such as denial-of-service simulation or testing shared provider infrastructure remain off-limits under each provider's acceptable use policy.
A cloud configuration review checks your settings against a benchmark, such as a CIS Benchmark, and flags deviations: an S3 bucket without Block Public Access enabled, an IAM role with an overly broad policy. It does not prove those deviations are exploitable. A cloud penetration test goes further: testers actively exploit the misconfigurations found, chaining them into a real attack path, for example combining an over-privileged Lambda execution role with an exposed metadata endpoint to escalate to full account administrator access. A configuration review tells you what is wrong. A penetration test proves what an attacker could actually do with it.
Yes, when scoped correctly. A full Microsoft 365 assessment tests Entra ID Conditional Access policies and legacy authentication bypass paths, Exchange Online mail flow and delegation rules, SharePoint and OneDrive sharing configuration, Teams external access and guest policies, and Intune device compliance controls. It is typically scoped and priced as its own engagement alongside or separate from AWS, Azure, or GCP testing, since M365 is a distinct tenant with its own identity model.
The leading UK cloud penetration testing companies in 2026 are Precursor Security, NCC Group, Pen Test Partners, Redscan (Kroll), JUMPSEC, OnSecurity, and LRQA. Each has a different strength: Precursor for published multi-cloud pricing and closed-loop detection, NCC Group and Redscan for enterprise scale, Pen Test Partners for hardware-adjacent cloud estates, JUMPSEC for NCSC CHECK-status public sector work, OnSecurity for fast PTaaS delivery, and LRQA for bundling cloud testing with wider ISO and PCI certification work.