Key Points
The National Cyber Security Centre (NCSC) has confirmed that Web Check and Mail Check will be retired by March 2026.
For many public sector teams, these services were the "easy button" for monitoring basic website risks and certificate issues. Now that you’re being asked to transition to a commercial alternative, you’re likely asking the same question: How do we keep that same level of visibility without adding complexity?
Meet Intruder…
As an alum of the NCSC Cyber Accelerator, we built Intruder to keep the simplicity you loved about Web Check, while providing the broader, always-on protection required for modern infrastructure. It’s the natural next step for organizations looking to close the gap Web Check leaves behind.
The threat landscape has changed (and so should your tools)
Web Check was designed to provide essential visibility at a time when the public sector had fewer options for affordable, accessible security tooling. But the threat landscape moves faster now.
As the NCSC steps back, this is your opportunity to move beyond basic checks and gain a clearer, complete view of your attack surface. Here is how Intruder upgrades your workflow:
1. See beyond the browser
Web Check was great for surface-level issues, but modern risks often hide deeper in your stack. Intruder monitors your entire attack surface - including cloud accounts, servers, and applications - checking for over 170,000 weaknesses. It’s the difference between checking if your front door is locked, and checking every window, vent, and back gate.
2. Quiet the noise
You don’t need a longer list of problems; you need to know what to fix first. Instead of drowning you in alerts, Intruder filters and prioritizes issues based on exploit likelihood and real world threat intelligence. We help you focus your limited resources on the issues that genuinely matter - something our customers (and reviewers on Gartner and G2) consistently cite as a game-changer.
3. Security that doesn't sleep
Web Check relied on manual prompts or fixed schedules. Intruder is continuous. We automatically scan whenever a new threat emerges or your environment changes. If a new vulnerability hits the headlines on a Friday night, Intruder is already checking if you’re affected.
4. Audit-ready, instantly
Cyber Essentials, ISO 27001, and SOC 2 all expect evidence of ongoing monitoring. Intruder’s reporting is designed with these frameworks in mind, giving you straightforward documentation you can share with auditors or internal stakeholders in seconds.
Trusted by the UK Public Sector
Intruder was founded in the UK and selected for the GCHQ Cyber Accelerator. We understand the unique pressure on public sector IT: you need enterprise-grade vigilance without the enterprise-grade headache.
We are already supporting government and public sector teams who need clearer visibility of their external footprint. As one customer recently shared:
“I can't recommend the service enough. Intruder flagged a critical vulnerability as actively exploited on our server on a Sunday evening. We were able to fix it by Monday morning.”
Senior security specialist, Healthcare
Why now is the right time to move
While the final retirement date is March 2026, transitioning early gives you time to onboard smoothly, understand your exposure, and avoid a frantic last-minute switch.
Intruder helps you:
- Discover exposed assets and unknown subdomains before attackers do.
- Scan websites, applications, cloud accounts, and infrastructure in one place.
- Prioritize real risks without drowning in false positives.
- Report to auditors with zero manual admin.
Whether you manage security for a small council or a large public sector organization, Intruder provides an efficient, intuitive and affordable solution.
Start your transition today
More than 3,000 organizations rely on Intruder for continuous vulnerability scanning and attack surface visibility. You can get set up and start your first scan in minutes.
Start your free 14-day trial and replace Web Check with a solution built for today’s threats. Plans start from as low as £113 per month.
