Fortra Email Security & Anti-Phishing vs KnowBe4 Cloud Email Security: Side-by-Side Comparison (2026)

Short answer

Mid-market and enterprise security teams drowning in phishing and BEC attacks will see immediate ROI from Fortra Email Security & Anti-Phishing because its DMARC enforcement and account takeover detection actually stop the attacks that make it past your initial filters. The platform covers five of the five NIST CSF 2.0 Protect and Detect functions, with particular strength in continuous monitoring and identity controls that catch lateral movement after compromise. Skip this if your organization needs a single unified email and web gateway; Fortra is email-focused and doesn't pretend otherwise. Mid-market and enterprise teams running Microsoft 365 should evaluate KnowBe4 Cloud Email Security primarily for its behavioral AI that catches business email compromise and anomalous sending patterns that signature-based filters routinely miss. Native M365 integration means zero infrastructure overhead, and the platform scores strongly on NIST DE.CM and DE.AE for continuous monitoring and incident analysis. Where it falls short: the user education and awareness features, while present, feel bolted on rather than integrated, so don't expect this to replace a dedicated security awareness platform.