Microsoft’s New Email Rules: What Agencies Need to Know

As of 5th May 2025, Microsoft is now enforcing stricter email authentication for high-volume senders targeting Outlook.com, Hotmail.com, and Live.com addresses. This aligns with similar measures by Google and Yahoo in 2024, marking a significant industry shift towards enhanced email security.

Key Requirements for Bulk Senders

If your agency sends over 5,000 emails daily, ensure the following are in place:

• SPF (Sender Policy Framework): Authorises specific servers to send emails on your behalf.
• DKIM (DomainKeys Identified Mail): Adds a digital signature to verify email authenticity.
• DMARC (Domain-based Message Authentication, Reporting, and Conformance): Publishes a policy (minimum p=none) to instruct email providers on handling unauthenticated messages.

Failure to comply may result in emails being rejected outright, not just relegated to spam folders.

Impact on Common Email Platforms

Platforms like Mailchimp, HubSpot, and Campaign Monitor require proper configuration to meet these standards. It’s essential to align your domain’s DNS records with these services to ensure deliverability.

Why This Matters

Without proper authentication:

• Deliverability Drops: Emails may not reach recipients.
• Reputation Risks: Unauthenticated emails can harm your domain’s credibility.
• Client Trust Erodes: Clients expect reliable communication; failures can damage relationships.

How We Can Help

At Cubit Technology, we assist agencies in:

• Configuring SPF, DKIM, and DMARC records.
• Ensuring alignment across email platforms.
• Monitoring and maintaining email deliverability.

If you’re unsure about your current setup or need guidance, we’re here to help.

For a more detailed breakdown and assistance, feel free to reach out.