The double-digit decline in the number of registered letters posted in South Africa stands in stark contrast to the growing use of email authentication.

ICASA’s State of the ICT Sector Report 2025, released in early April 2026, notes that registered letters declined to 142m posted last year. Five years ago, registered letters numbered a substantial 326m.

Email authentication is emerging as a key enabler of trusted message delivery. Protocols like Domain-based Message Authentication, Reporting, and Conformance (DMARC) offer higher deliverability, and better security, compared to anything a postal service could offer.

“Email authentication is today so effective in ensuring the successful delivery of emails that the registered letter is being consigned to niche applications,” says Adriaan Venter, CEO of Cube ICT Solutions.

A nationwide managed ICT services provider, Cube ICT Solutions sees the potential of email authentication as going beyond successful delivery. 

“Verified logos, proactive threat detection, regulatory compliance and more will soon make an appearance on corporate emails. These are all desirable digital features that will further consign registered letter use to those legally required to send them,” Venter adds.

After domain owners adopt authenticated email protocols like DMARC to verify their identities, prevent phishing and confirm that subsequent emails haven’t been tampered with in-transit, small and large enterprises alike find that delivery rates skyrocket as their emails avoid spam folders.

However, when it comes to reliable delivery, email authentication is only one side of the coin. “Organisations need visibility into how their domains are performing in order to maintain trust and reliability,” explains Venter.

To support this, Cube ICT Solutions has introduced an online domain assessment tool that enables organisations to evaluate their email security posture and reputation. The tool analyses authentication protocols, domain configuration and blacklist status to identify potential risks that may impact deliverability: https://cubeict.co.za/dmarc-tester/

Clicking above will perform an automated audit of a domain's security posture and reputation.

By checking for the presence of email authentication protocols, scanning domain name settings that could make email unreachable, checking if your domain is blacklisted, Cube ICT Solutions will be able to determine if your domain is properly configured, secure from attacks and trusted for delivery by email providers.

The shift toward authenticated email reflects a broader trend in which trust, security, and verifiability are becoming central to digital communication.

As organisations increasingly rely on email for operational and customer engagement purposes, ensuring reliable delivery is becoming a business priority.

“In practical terms, undelivered emails ultimately translate into missed opportunities and potential revenue loss,” concludes Venter.