Click-Through Rate

Click-through rate was once a simple metric: clicks / delivered. Then link-scanning gateways became standard. Microsoft Safe Links, Mimecast URL Protect, and Proofpoint TAP all pre-fetch every link in every email for malware scanning. The result is automated clicks fire from the security gateway, not a human, often within seconds of delivery.

How to calculate trustworthy CTR

• Use unique clicks per recipient, not total clicks. The scanner often fires once; a real human firing twice should count as one unique click.
• Filter clicks by source. Known scanner IP ranges and User-Agents should be excluded from the count.
• Time-window the count. A click within 5 seconds of delivery is almost always a scanner. A click 2 hours after delivery is almost always a human.

B2B benchmarks in 2026

For cold outbound:

• Below 1 percent: low-engagement or off-target list
• 1-3 percent: typical for well-targeted cold lists
• 3-7 percent: strong. either high relevance or warm-list dynamics
• Above 7 percent: warm list or counting scanner clicks in the numerator

These are unique-human-click CTRs after scanner filtering. Without filtering, every benchmark roughly doubles and the metric loses meaning.