- KnowBe4 Prevent
Best for: Teams worried about misdirected email
It earns a place because it targets human mistakes, such as the wrong recipient or the wrong file, and it warns the sender in Outlook before the email leaves. That fits a Microsoft 365 company whose main worry is careless sends, though it also flags deliberate ones. Weigh how often users will see a warning in a normal week, because a prompt people learn to click past stops protecting you.
From Best Email DLP Solutions for Business, Fall 2026
- Trustifi Outbound Shield
Best for: Companies that must encrypt regulated data
Trustifi is here because it turns a detection into encryption, so sensitive mail still goes out but arrives protected, which suits regulated companies working under HIPAA, GDPR or CCPA. Because it runs on several mail platforms, it also covers mixed setups. Check how people outside your company experience the one-click decrypt and the extra verification step before you roll it out.
From Best Email DLP Solutions for Business, Fall 2026
