B2B Cold Email Deliverability, Open & Reply Rates (2026)
Standard industry metrics across 2.4M tracked B2B cold emails sent via secondary Google Workspace and Microsoft 365 domains.
📊 Conversion & Performance Metrics
| Metric | Target Baseline | Warning Threshold |
|---|---|---|
| Average Open Rate | 55% – 70% | < 45% (Indicates spam filtering) |
| Average Reply Rate | 5.5% – 9.2% | < 3.0% (Weak value proposition/ICP) |
| Positive / Interested Reply Rate | 1.8% – 3.5% | < 1.0% |
| Hard Bounce Rate | < 1.5% | > 2.0% (Risk of domain suspension) |
| Spam Complaint Rate | < 0.05% | > 0.1% (Immediate ISP penalty) |
🛡️ Essential Rules of Thumb
- Send maximum 30 emails/day per mailbox across rotating secondary domains.
- Always set up SPF, DKIM, and DMARC with p=quarantine or p=reject.
- Use Custom Tracking Domains (CTD) on a separate sub-domain (e.g. track.outreachdomain.com).