What are the organizational costs of undelivered email?

Key findings

• Hidden costs: Undelivered emails incur costs not just in wasted marketing spend but also in lost opportunities, increased customer service inquiries, and compromised data integrity, which are often harder to quantify.
• Reputation damage: Consistent undeliverability, whether through bounces or spam folder placement, can severely damage a sender's reputation, leading to lower inbox placement rates for all future communications. This can also result in your domain or IP being added to an email blacklist (or blocklist).
• Resource drain: Internal teams spend valuable time and resources re-engaging subscribers, re-sending messages, and debugging complex deliverability issues instead of focusing on core business activities.
• Lost revenue: Marketing, sales, and transactional campaigns fail to reach their intended audience, directly impacting sales, lead generation, customer onboarding, and retention. You can learn more about how to calculate the monetary value of email deliverability.
• Data inaccuracy: Poor deliverability metrics often signal an unhealthy or outdated email list, leading to inaccurate analytics and misinformed strategic decisions. Addressing this often involves understanding the costs of email list validation tools.

Key considerations

• Defining 'undelivered': It's crucial to distinguish between hard bounces (emails completely rejected) and emails that land in the spam or junk folder. Both represent a failure to reach the recipient's primary inbox and carry organizational costs.
• Proactive list hygiene: Implementing regular email list validation and sunsetting inactive subscribers can significantly reduce bounce rates and improve overall deliverability performance.
• Monitoring metrics: Go beyond basic open and click rates. Closely monitor bounce rates, spam complaint rates, and inbox placement across various email service providers to identify issues early.
• Authentication protocols: Proper implementation of email authentication protocols like SPF, DKIM, and DMARC is fundamental to ensuring legitimate emails are recognized and reach the inbox. Poor authentication is a leading cause of undelivered mail, as highlighted in Kickbox's Email Deliverability Report.

Key opinions

• Visibility is key: If an email isn't seen by the recipient, all efforts put into planning, crafting, and designing it are effectively wasted.
• Wasted resources: Time, talent, and budget invested in email copy, design, segmentation, and automation are lost if messages consistently fail to reach the inbox.
• Perception of failure: Campaigns with low deliverability or high spam placement are perceived as unsuccessful, regardless of the quality of the content or offer within the email.
• Engagement impact: Undelivered emails mean zero engagement, leading to missed sales, diminished customer relationships, and a failure to nurture leads through the marketing funnel.

Key considerations

• Focus beyond opens/clicks: Marketers must expand their reporting to include inbox placement rates and delivery success rates, rather than solely relying on engagement metrics that only track delivered mail.
• Collaboration with technical teams: Work closely with IT, deliverability specialists, or email service providers to ensure the technical setup (e.g., proper DMARC implementation) supports marketing goals and prevents email deliverability issues. This is crucial for fixing issues like emails going to spam.
• Audience data quality: A clean, engaged email list is foundational to good deliverability. Marketers should prioritize strategies to maintain list health, recognizing that sending to unengaged subscribers hurts overall performance.
• Impact on future campaigns: Poor deliverability in one campaign can negatively affect the sender reputation and the performance of all subsequent email sends, creating a compounding negative effect. Forbes highlighted this in their article Is Undelivered Email Costing You Money?.

Key opinions

• Beyond spam: True undelivered messages are those that bounce or are outright rejected, not just those that land in the spam folder (which are technically 'delivered').
• Cascading effects: Leaving undeliverable emails (especially hard bounces) unaddressed will eventually lead to being blacklisted or blocklisted, compounding the amount of undeliverable email and increasing its cost.
• Technical vs. marketing view: While marketers view spam folder delivery as a failure, from a technical viewpoint, it is still considered delivery. However, both have negative organizational impacts.
• Sender reputation erosion: A high rate of undeliverable messages, particularly to non-existent users (dead domains), signals poor list quality to ISPs and damages sender reputation. This in turn reduces overall inbox placement for all subsequent mailings. Learn more about how sending to dead domains affects deliverability.

Key considerations

• Distinguish bounce types: Properly classify and handle hard bounces versus soft bounces. Hard bounces indicate permanent failures and require immediate removal of the address from the list.
• Monitor blocklists: Regularly check your IP and domain against common blacklists and blocklists using a reliable blocklist checker. Being listed can severely impact delivery to all recipients.
• Implement DMARC: Strong email authentication (SPF, DKIM, DMARC) is crucial for proving sender legitimacy. Failure to implement these correctly can lead to emails being marked as suspicious, affecting deliverability, as discussed by experts at Word to the Wise.
• Proactive monitoring: Utilize deliverability monitoring tools to gain insights into bounce rates, spam complaint rates, and inbox placement across various ISPs, allowing for early detection and resolution of issues. This is especially important for sending to old inactive profiles.

Key findings

• Quantifiable losses: Industry reports and official bodies frequently put a specific dollar figure on the cost per undeliverable item, demonstrating the tangible financial drain on businesses.
• Reprocessing costs: Undelivered items (including emails) often necessitate additional effort for correction, re-sending, and follow-up, incurring significant operational overhead.
• Lost business: The failure to reach customers or prospects directly translates into missed sales, uncollected payments, and damaged customer relationships, leading to measurable revenue loss.
• Industry benchmarks: Organizations and research frequently establish benchmarks for acceptable undeliverable rates, implying that exceeding these can lead to disproportionate costs and problems.

Key considerations

• Data accuracy validation: The primary cause of many undeliverable messages stems from inaccurate or outdated contact information, emphasizing the importance of robust data management practices.
• Automated bounce handling: Implementing systems that automatically process and remove bounced email addresses is critical for maintaining list hygiene and preventing ongoing reputation damage.
• Compliance impact: For transactional emails (e.g., invoices, legal notices), non-delivery can lead to serious compliance issues, financial penalties, and legal repercussions.
• Holistic deliverability strategy: Effective deliverability requires a comprehensive approach, combining proper email authentication like DMARC, SPF, and DKIM, rigorous list hygiene (avoiding spam traps), and engaging content.