How BIMI Enhances Email Security and Brand Trust

Brand Indicators for Message Identification (BIMI) is an email authentication protocol designed to enhance email security while reinforcing brand trust. BIMI allows organizations to display their verified logo alongside authenticated emails, helping recipients distinguish legitimate messages from phishing attempts.

While SPF (Sender Policy Framework), DKIM (DomainKeys Identified Mail), and DMARC (Domain-based Message Authentication, Reporting & Conformance) provide foundational email authentication, BIMI adds a visual trust indicator that improves security and brand recognition. This article explores how BIMI works, its security benefits, and best practices for implementation.

What is BIMI and How Does It Work?

BIMI builds upon DMARC enforcement by allowing email senders to display their official brand logo next to authenticated messages. For BIMI to work:

The sender’s domain must have a DMARC policy with p=quarantine or p=reject.
A BIMI DNS record must be published.
The brand logo must be hosted in SVG format.
Some mailbox providers require a Verified Mark Certificate (VMC) to confirm logo ownership.

Example of a BIMI DNS Record:

v=BIMI1; l=https://logo.example.com/logo.svg;

How BIMI Strengthens Email Security

Adds a Visual Authentication Layer

Recipients see a trusted logo in their inbox, making it easier to identify legitimate emails.
Reduces the risk of phishing and email impersonation.

Requires DMARC Enforcement

BIMI mandates a DMARC policy set to quarantine or reject, ensuring that unauthenticated emails are blocked or flagged.
Helps organizations improve their DMARC compliance while benefiting from visual authentication.

Enhances Brand Protection

Prevents cybercriminals from misusing brand logos in fraudulent emails.
Ensures only verified brands can display their logo, reducing brand abuse.

Implementation Guide for BIMI

Step 1: Enforce DMARC Policy

Ensure SPF and DKIM are properly configured.
Set DMARC policy to p=quarantine or p=reject.

Step 2: Create an SVG Logo

The logo must be square and SVG Tiny Portable/Secure (SVG P/S) format.
Ensure the logo is hosted on an HTTPS server.

Step 3: Obtain a Verified Mark Certificate (VMC) (Optional)

Some email providers (e.g., Gmail) require a VMC issued by a trusted certificate authority (CA).

Step 4: Publish the BIMI DNS Record

Example BIMI TXT Record:

  v=BIMI1; l=https://logo.example.com/logo.svg;

Step 5: Test and Monitor

Use BIMI testing tools to check implementation.
Monitor email deliverability and security reports.

The Impact of BIMI on Email Engagement & Security

Increases Email Open Rates

Studies show that users are more likely to open emails with brand logos.
Enhances recipient confidence in email authenticity.

Reduces Brand Impersonation

Ensures that only verified brands can display their logo.
Helps prevent phishing attacks that rely on fake branding.

Strengthens Email Provider Trust

Encourages email providers to prioritize authenticated messages.
Reduces the likelihood of emails being marked as spam.

BIMI is a powerful addition to email authentication, complementing SPF, DKIM, and DMARC by providing a visual trust layer. By ensuring DMARC compliance, securing a Verified Mark Certificate, and properly implementing BIMI, organizations can boost email engagement, enhance security, and protect their brand from impersonation.

Check Your Domain’s Email Authentication Setup

To check if your SPF, DKIM, DMARC, and BIMI configurations are correct, use these tools:

Need Expert Consultation?

For professional assistance in configuring SPF, DKIM, DMARC, and BIMI, contact Emre Savas on LinkedIn.