In today’s increasingly privacy-conscious digital world, trust is the currency that powers successful email marketing. That was the central theme of the recent webinar hosted by Netcore, where James Deacon, Principal Email Deliverability Consultant at Netcore, held a deep-dive conversation with guest Franziska Kuper, Customer Success Manager at the Certified Senders Alliance (CSA).

The session went beyond typical slide decks and buzzwords, offering instead a dynamic, insightful conversation on how marketers can build lasting, trust-based relationships with both mailbox providers and subscribers. Here’s a summary of the most valuable insights.

Why Trust Matters More Than Ever

Franziska defined trust in email through two lenses:

1. Mailbox providers (ISPs) must trust that you’re a legitimate, well-configured sender.

1. Subscribers must trust that what lands in their inbox is valuable and relevant.

Without both layers of trust, your emails risk being ignored – or worse – classified as spam.

“You’re almost guilty until you’re proven innocent,” said Netcore’s James, emphasizing the importance of warming up IPs and demonstrating positive sending behavior from the start.

Engagement Is the New Currency

Gone are the days when IP reputation alone determined inbox placement. Today, domain reputation and user engagement carry significant weight.

Mailbox providers evaluate:

• Opens and clicks

• Time spent reading

• Replies and forwards

• Negative signals (e.g. spam reports or instant deletions)

These behaviors provide ISPs with strong indicators about whether a sender is trustworthy and whether recipients want their emails.

“Even unsubscribes are better than spam complaints – at least the user is engaging with your email,” Franziska noted.

The Role of Technical Infrastructure

Trust starts with the basics:

• Proper authentication (SPF, DKIM, DMARC)

• A clean sending infrastructure

• Transparent unsubscribe mechanisms

• Compliance with Gmail/Yahoo sender guidelines

Franziska highlighted that mailbox providers now publish technical criteria openly, and not meeting them could cause deliverability penalties, even if your content is excellent.

Data Without Insight is Useless

One underutilized action marketers can take is deeply analyzing unsubscribe and complaint data.

Franziska recommends segmenting unsubscribers by:

• Mail type (e.g. newsletters vs. promotions)

• Tenure (e.g. users who unsubscribe after X months)

• Device or region

From there, marketers can:

• Adjust frequency

• Rethink automation flows

• Tailor retention strategies (e.g. a special re-engagement offer)

“Negative signals are still engagement. Don’t ignore them – learn from them.”

Why CSA Certification Matters

While good email practices can exist without certification, being CSA certified offers key benefits:

• Signals trust to mailbox providers

• Enables access to exclusive data (like complaint rates)

• Helps senders during peak seasons (e.g. Black Friday) by improving throughput

• Shows commitment to industry standards and transparency

CSA doesn’t “whitelist” senders, but its certification acts as a trusted signal, especially for high-volume marketers.

What About AI?

The panel briefly touched on the increasing role of AI in email marketing. Used responsibly, AI can:

• Generate content ideas or structures

• Help with segmentation

• Assist in analyzing behavioral data

However, if abused to simply send more emails faster, AI will harm sender reputation, not help it.

Final Advice for Marketers

Franziska’s closing tip? Consistency and self-awareness.

• Don’t radically change volumes overnight

• Monitor patterns over time

• Focus not just on what you send, but what your users actually want

“Email trust can take months to build and days to destroy.”

Key Takeaways

• Trust is built with both ISPs and subscribers, and both matter equally

• Engagement signals (positive and negative) are crucial indicators

• CSA certification strengthens sender reputation and transparency

• AI is a tool, not a shortcut. Use it strategically, not recklessly

• Analyze your unsubscribe & complaint data – it’s full of opportunity

To dive deeper into the insights shared, watch the full webinar on demand or explore how CSA certification can elevate your email strategy.