Essential Statistics

• Cold emails led to 25.6% spam complaints and 17.7% unsubscribes.
• Affiliate emails saw the highest unsubscribe rate at 19.5%.
• Event/webinar invitations and press announcements also underperformed.
• Thank you and reminder emails had the lowest complaints and unsubscribes.
• Spam complaints often closely track unsubscribe rates.

Key Takeaways

• Not all emails are equal—some hurt your list health more than others.
• Cold outreach and affiliate promos are major churn drivers.
• Transactional and relational emails perform much better.
• Overused formats like press announcements wear thin quickly.
• Low-value messages get flagged or ignored, damaging deliverability.

Actionable Insights

Reevaluate cold outreach tactics.

Cold emails top the spam complaint list—only send when there’s a clear value exchange.

Prioritize relationship-building emails.

Thank-you and reminder emails perform best—lean into messages that serve rather than sell.

Audit and segment your email lists.

Send press announcements and promotions only to highly engaged segments to minimize churn.

Test educational content alternatives.

Substitute pure promos with helpful content to reduce list fatigue.

Watch your complaint-to-unsubscribe ratio.

High spam flags indicate a deeper trust issue—your messaging may be misaligned.