Email marketing remains one of the most powerful channels for customer engagement, but ensuring that messages actually reach inboxes is becoming increasingly challenging. With advanced spam filters, AI-driven detection algorithms, and stricter email authentication standards, brands must adopt best practices and cutting-edge solutions to maintain strong email deliverability. Here’s how leading marketers at the Digital Marketing Solutions Summit are navigating email authentication, sender reputation management, and engagement-based strategies to ensure their messages land where they belong – in the inbox…

1. Strengthening Email Authentication with DMARC, SPF, and DKIM

Email authentication is critical in preventing phishing attacks, email spoofing, and domain abuse, which can significantly impact a sender’s reputation. To improve deliverability, UK brands are adopting:

✔ Domain-based Message Authentication, Reporting, and Conformance (DMARC) – Helps businesses prevent email fraud and provides visibility into how their domain is being used.
✔ Sender Policy Framework (SPF) – Allows organisations to authorise specific email servers to send messages on their behalf, reducing the likelihood of spoofing.
✔ DomainKeys Identified Mail (DKIM) – Adds a cryptographic signature to email headers, helping email providers verify that messages haven’t been altered.

These authentication protocols ensure better inbox placement and stronger brand trust, particularly as email security policies become more stringent.

2. Managing Sender Reputation for Higher Deliverability

Email providers like Google, Microsoft, and Yahoo now evaluate sender reputation scores to determine whether an email reaches an inbox or is flagged as spam. Key strategies to maintain a positive sender reputation include:

✔ Keeping bounce rates low – Regularly cleaning email lists to remove invalid, inactive, or spam-trap addresses.
✔ Avoiding spam trigger words – Overuse of phrases like “free trial,” “urgent,” or excessive exclamation points (!!) can lower deliverability rates.
✔ Using dedicated IP addresses – Separating transactional emails from marketing emails helps maintain a stable sender reputation.

A strong sender reputation ensures that ISPs and email clients recognise a brand’s emails as legitimate and trustworthy.

3. Engagement-Based Deliverability: Moving Beyond Open Rates

With Apple’s Mail Privacy Protection (MPP) and other privacy-focused updates, open rates are no longer reliable indicators of engagement. Instead, email providers prioritise:

✔ Click-through rates (CTR) – Encouraging interactive elements, such as surveys or CTA buttons, improves engagement scores.
✔ Reply rates – More conversational, user-friendly emails that encourage replies can boost deliverability rankings.
✔ Inbox placement testing – Using tools like GlockApps or Litmus helps brands understand where emails are landing (inbox, spam, or promotions folder).

Conclusion

In 2025, overcoming spam filters requires a proactive and data-driven approach. By strengthening authentication protocols, maintaining sender reputation, and optimising engagement-based metrics, brands can significantly improve email deliverability. With these best practices in place, email remains a high-performing channel for customer engagement, retention, and revenue generation.

Are you searching for Email Marketing solutions for your organisation? The Digital Marketing Solutions Summit can help!

Photo by Brian J. Tromp on Unsplash