Key Metrics to Monitor During Your Email Warm-Up Journey

The Ikonn Blog
2 min read

When warming up your email address for B2B campaigns, success doesn’t come down to guesswork—it’s all about the data. Tracking key metrics during your warm-up phase ensures that your email reputation builds steadily, deliverability improves, and ISPs recognize you as a trusted sender.

Here’s an in-depth look at the essential metrics to monitor and how they can guide your warm-up strategy.

1. Bounce Rates: The Gatekeeper Metric

A bounce occurs when an email fails to reach the recipient’s inbox. High bounce rates during warm-up can significantly harm your sender reputation.

What to Watch:

  • Soft Bounces: Temporary issues like a full inbox or server downtime.
  • Hard Bounces: Permanent issues like invalid or non-existent email addresses.

Best Practice:
Use email verification tools to clean your list before sending. During warm-up, keep your bounce rate below 2% to avoid triggering ISP alarms.

2. Spam Complaints: A Red Flag for ISPs

Spam complaints occur when recipients mark your email as spam, signaling to ISPs that your emails might not be welcome.

What to Watch:

  • Track the percentage of emails flagged as spam (keep it below 0.1%).

Best Practice:
Send to highly engaged contacts during warm-up and provide an easy way for recipients to unsubscribe rather than marking emails as spam.

3. Inbox Placement Rates: The End Goal

Inbox placement rate is the percentage of emails that land in the recipient’s inbox versus the spam folder or being blocked entirely.

What to Watch:

  • Aiming for a 90%+ inbox placement rate is ideal during warm-up.

Best Practice:
Use deliverability monitoring tools like GlockApps or EmailConsul to track inbox placement across major ISPs like Gmail, Outlook, and Yahoo.

4. Engagement Metrics: Building Positive Signals

Engagement metrics include open rates, click-through rates (CTR), and replies. ISPs prioritize emails that recipients actively interact with.

What to Watch:

  • Open Rates: Aim for 20%+ during warm-up.
  • CTR: A consistent 2-3%+ indicates good engagement.

Best Practice:
Start with personalized, relevant emails to your most loyal or active audience. Encourage replies or clicks to drive positive engagement.

5. Delivery Rates: A Foundational Metric

Delivery rate is the percentage of emails successfully delivered to recipients, excluding bounces.

What to Watch:

  • Maintain delivery rates above 98% throughout the warm-up.

Best Practice:
Authenticate your domain with SPF, DKIM, and DMARC (more on this in the next blog post) to prevent deliverability issues.

6. Reputation Metrics: Monitoring Sender Trust

Some tools provide metrics on sender reputation, giving you insight into how ISPs perceive your email-sending practices.

What to Watch:

  • Tools like Google Postmaster Tools or Microsoft SNDS for IP/domain reputation scores.

Best Practice:
Check these regularly during warm-up to identify and address any issues early.

Key Takeaway: Data Guides Warm-Up Success

Tracking these metrics during warm-up isn’t just about improving one campaign—it’s about establishing a foundation for long-term deliverability success.

At Ikonn Media, we specialize in guiding B2B marketers through the warm-up process, ensuring every metric points to success. Contact us today to optimize your warm-up journey!

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