Mimecast Web Security is going away. Here's the timeline.

Why Mimecast is stepping back

Mimecast's own end-of-life notice gives the reason: retiring Web Security lets it concentrate investment on human risk, email security, governance and compliance, and data protection. Web security is no longer part of its plan, it names no successor product, and customers are referred to their account manager to choose a replacement.

What to do before 2 August 2027

First, decide scope: the web layer only, or the platform it sits on. The steps below work either way.

Then three practical steps from the notice itself: re-point your DNS away from Mimecast before the shutdown, export any historical logs you need to keep, and retrieve your agent uninstaller passwords while the service can still hand them over. Then pick the replacement on your timetable, not the deadline's.

What a smart transition looks like

The best replacements don't just match the feature list, they simplify it and connect it. When you evaluate alternatives, look for: real-time protection from malware, ransomware and phishing; inline content control and productivity filtering; cloud app visibility and governance; integration with email security and DLP; and lightweight deployment.

And critically, a platform that doesn't require rebuilding everything from scratch.

TrustLayer Browse: the seamless replacement

Browse gives you full control over web traffic, file movement and cloud app access, smarter detection, real-time enforcement, zero proxy overhead. Malicious sites blocked, risky downloads stopped, unwanted content filtered before it hits the browser.

It works as part of the TrustLayer Platform, integrating web filtering with your email, identity and posture security in one place. Inline traffic inspection, behavioural detection with AI-powered risk scoring, flexible upload and download controls, productivity and compliance filters, and full visibility over cloud app use.

Browse is one of four layers. If Mimecast also handles your email, replacing the web layer is a reasonable moment to look at whether mail, users and Microsoft 365 posture should sit on the same platform and the same policy model, rather than spreading across three vendors and three consoles. TrustLayer as a Mimecast alternative →

Don't wait for the shutdown

Ten months sounds like plenty until renewals, procurement and a rollout have to fit inside it. Whether you need a full platform transition or just the web layer replaced, start now, and the deadline becomes a non-event.