The best cloud access security broker UK businesses can deploy in 2026 comes down to what's already running in your stack. Microsoft Defender for Cloud Apps wins for Microsoft 365-native businesses, Netskope wins for enterprises consolidating CASB into a full SSE platform, and Forcepoint ONE wins for hybrid and remote workforces that need one console for network and cloud policy. Skyhigh Security takes multi-cloud data protection, Palo Alto Networks Prisma SaaS takes shops already running Palo Alto firewalls, and Lookout Cloud Security takes mobile-first, BYOD-heavy teams.
Why this matters
A cloud access security broker sits between your staff and the SaaS apps they use — Microsoft 365, Salesforce, Google Workspace, Slack — and enforces policy on data leaving those apps. For UK businesses, the trigger is usually external: a client security questionnaire, a Cyber Essentials Plus renewal, or an ISO 27001 auditor asking how you control shadow IT.
Most teams shopping for a CASB in 2026 aren't doing it for its own sake. They're closing a gap flagged during certification work, and OneClickComply sees this pattern constantly across ISO 27001 and SOC 2 engagements: the CASB gets bought, but nobody maps its logs back to the control it's supposed to satisfy.
That's the gap this guide closes. Below is a ranked, honest comparison of the CASB options UK businesses actually deploy in 2026 — not a vendor list, a decision tree.
What makes the best CASB
- Shadow IT discovery — how many SaaS apps it identifies from network and log traffic without agents
- Data loss prevention granularity — file-level, not just login-event, control
- Identity integration — how cleanly it plugs into Entra ID, Okta, or Google Workspace SSO
- Multi-cloud reach — coverage across AWS, Azure, and GCP, not just SaaS apps
- Policy management overhead — how much ongoing tuning a lean security team has to do
- Audit mapping — whether its reporting lines up with ISO 27001 Annex A, SOC 2 CC6, or Cyber Essentials requirements
Cloud access security broker UK options at a glance
| Tool | Best for | Standout feature | Key limitation |
|---|---|---|---|
| Microsoft Defender for Cloud Apps | Microsoft 365-native businesses | Native Entra ID and Purview integration | Weaker outside the Microsoft ecosystem |
| Netskope | Enterprises converging CASB and SSE | Real-time inline DLP across web and cloud | Overkill for a five-person security function |
| Skyhigh Security | Multi-cloud data protection | Deep AWS, Azure, GCP posture visibility | Steeper setup than app-only CASBs |
| Palo Alto Networks Prisma SaaS | Teams on Palo Alto firewalls | Single console with existing NGFW policy | Less useful without a Palo Alto network already in place |
| Forcepoint ONE | Hybrid and remote workforces | Combines CASB, SWG, and ZTNA in one agent | Newer unified platform, fewer long-term references |
| Lookout Cloud Security | Mobile and BYOD-heavy teams | Mobile endpoint risk feeds cloud access decisions | Narrower scope than full SSE platforms |
1. Microsoft Defender for Cloud Apps: best for Microsoft 365-native businesses
Defender for Cloud Apps is Microsoft's built-in CASB, and it reads directly off Entra ID sign-in logs and Microsoft Purview data classifications. For a UK business already on Microsoft 365 E5, it's the path of least resistance — no new identity integration, no separate agent rollout.
Microsoft Defender for Cloud Apps pros:
- Ships inside Microsoft 365 E5 licensing, so no separate vendor relationship
- Purview labels carry straight through to DLP policy
- Conditional access ties cloud app risk directly to sign-in decisions
Microsoft Defender for Cloud Apps cons:
- Shadow IT discovery outside Microsoft's own app catalogue is thinner than dedicated CASB vendors
- Policy tuning UI is less intuitive than Netskope's for complex rule sets
Best for: UK SMEs and mid-market firms already standardised on Microsoft 365. Verdict: Buy.
2. Netskope: best for enterprises consolidating CASB into SSE
Netskope built its name on inline, real-time DLP that inspects traffic as it moves, not after the fact. In 2026 it positions itself as a full security service edge platform, with CASB as one module alongside secure web gateway and zero trust network access.
Netskope pros:
- Inline inspection catches data movement other CASBs only log retrospectively
- One platform replaces several point tools (SWG, CASB, ZTNA)
- Strong app risk scoring across thousands of cataloged SaaS apps
Netskope cons:
- Deployment and tuning need dedicated security engineering time
- Licensing complexity scales with the number of modules turned on
Best for: Enterprises replacing multiple network and cloud security tools with one platform. Verdict: Buy for scale, Hold for lean teams.
3. Skyhigh Security: best for multi-cloud data protection
Skyhigh Security (formerly McAfee MVISION Cloud) focuses on data protection across AWS, Azure, and Google Cloud infrastructure, not just SaaS apps. That makes it the stronger pick when the risk isn't Slack and Salesforce, it's misconfigured storage buckets and IAM roles.
Skyhigh Security pros:
- Cloud security posture management reaches infrastructure, not only apps
- DLP policies apply consistently across structured and unstructured cloud data
- Established track record across regulated industries
Skyhigh Security cons:
- Initial configuration takes longer than app-only CASBs
- Interface feels dated next to newer SSE-native platforms
Best for: Businesses running workloads across multiple public clouds. Verdict: Buy.
4. Palo Alto Networks Prisma SaaS: best for existing Palo Alto shops
Prisma SaaS extends Palo Alto's next-gen firewall policy into the cloud, which matters if your network security is already built on Palo Alto hardware or Prisma Access. It's a natural extension rather than a new vendor relationship.
Prisma SaaS pros:
- Single policy framework spans network and cloud app control
- Strong app classification database inherited from Palo Alto's firewall telemetry
- Reduces vendor sprawl for teams already committed to the ecosystem
Prisma SaaS cons:
- Limited standalone value if you're not already on Palo Alto infrastructure
- Licensing tied closely to existing Palo Alto contracts
Best for: UK businesses with Palo Alto firewalls already in place. Verdict: Buy if invested, Skip otherwise.
5. Forcepoint ONE: best for hybrid and remote workforces
Forcepoint ONE bundles CASB, secure web gateway, and zero trust network access into a single lightweight agent — built for a workforce split between office, home, and client sites rather than a single corporate network perimeter.
Forcepoint ONE pros:
- One agent covers CASB, SWG, and ZTNA without stacking separate tools
- Simpler licensing model than piecing together modules from a larger platform
- Built with hybrid work as the default assumption, not an add-on
Forcepoint ONE cons:
- Shorter market track record than Microsoft, Netskope, or Skyhigh
- Smaller partner and integration ecosystem
Best for: Distributed UK teams without a fixed office perimeter. Verdict: Hold — reassess after a longer deployment history.
6. Lookout Cloud Security: best for mobile and BYOD-heavy teams
Lookout built its reputation on mobile endpoint risk, and its cloud access security broker product feeds that mobile risk signal straight into cloud access decisions — useful when staff are logging into SaaS apps from personal phones and tablets more than laptops.
Lookout pros:
- Mobile risk scoring directly informs cloud access policy
- Strong fit for BYOD-first or field-service workforces
- Lighter footprint than full SSE suites
Lookout cons:
- Narrower scope than Netskope or Skyhigh outside the mobile use case
- Less depth on infrastructure-level cloud security posture
Best for: Field sales, healthcare, and logistics teams running mostly on mobile devices. Verdict: Buy for mobile-first fleets, Skip if desktop-first.
Turn CASB logs into audit evidence
Automate the ISO 27001 and SOC 2 mapping your CASB alone won't produce.
How we ranked these
Each cloud access security broker UK option above is scored against the six criteria listed earlier — shadow IT discovery, DLP granularity, identity integration, multi-cloud reach, policy overhead, and audit mapping. None of these tools scores highest on every dimension, which is the point: the right CASB depends on what's already in your stack, not a single leaderboard.
Which cloud access security broker should you choose?
If you're already on Microsoft 365 E5, start with Microsoft Defender for Cloud Apps — it's the lowest-friction path and the licensing is likely sunk cost already. If you're consolidating three or four security tools into one platform, Netskope justifies the heavier setup. If your risk sits in cloud infrastructure rather than SaaS apps, Skyhigh Security covers ground the others don't.
Whatever you pick in 2026, the CASB itself won't produce the audit trail an ISO 27001 assessor or SOC 2 auditor wants to see. That mapping work — turning access logs into control evidence — is where most UK businesses stall after the CASB is already live. Reviewing your cloud security configuration review programme alongside the CASB rollout closes that gap before an auditor finds it for you.
Frequently asked questions
One last thing
Most UK businesses that buy a cloud access security broker in 2026 do it after a client security questionnaire flags shadow IT as a gap — not before. The CASB solves the visibility problem; it doesn't automatically hand you the ISO 27001 or SOC 2 evidence an auditor wants to see mapped to a control number. Budget for that mapping step separately, or it becomes next year's audit finding all over again.