BIMI (Brand Indicators for Message Identification)
What is BIMI?
BIMI stands for Brand Indicators for Message Identification. It’s a recent and emerging industry-backed email authentication standard that allows brands to display their logo next to authenticated emails. The logo will be displayed in all BIMI supported email clients. BIMI helps improve brand trust, brand recognition, and engagement while also enabling stronger email security practices.
BIMI works on top of DMARC, SPF, and DKIM, ensuring that only legitimate and authenticated senders can display the logo. BIMI in supported clients means:
Authenticated email + verified logo = visible brand indicator in inbox.
Unauthenticated email = no logo.
Why is BIMI important for businesses?
It strengthens email security
BIMI requires strict DMARC enforcement, which in turn needs SPF and DKIM authentication. This pushes brands to adopt best-practice authentication and reducing email attacks like spoofing.
It improves brand trust
Seeing a verified logo reassures recipients that the email is genuinely from your brand. The logo allows recipients to distinguish between legitimate emails from your and a phishing attack.
It increases engagement
Emails with recognizable logos help users identify trusted senders faster. This makes it more likely that the customer will engage with your email knowing that it’s trustworthy.
It enhances inbox visibility
With loads of emails from businesses pouring into inboxes every day, standing out means the difference between an opened email or an ignored one. In crowded inboxes, BIMI adds a visual cue that differentiates branded emails from generic ones.
How does BIMI work?
An email is sent from a domain configured with SPF, DKIM, and DMARC.
DMARC passes with a policy of quarantine or reject.
The receiving mailbox provider checks for a BIMI DNS record.
The provider verifies the SVG logo (and VMC, if required).
If all checks succeed, the brand logo is displayed in the inbox.
BIMI prerequisites
To implement BIMI, the following elements are mandatory:
1. SPF (Sender Policy Framework) : Authorizes which servers can send email on behalf of your domain.
2. DKIM (DomainKeys Identified Mail) : Cryptographically signs outgoing messages to ensure integrity.
3. DMARC (Domain-based Message Authentication, Reporting & Conformance) : Defines how receivers should handle emails that fail SPF/DKIM checks.
Important: DMARC must be set to p=quarantine or p=reject. p=none is not sufficient for BIMI.
4. BIMI-compatible SVG logo :
Square format
SVG tiny 1.2
No scripts, animations, or external references
5. Verified Mark Certificate (VMC) (required by some providers) : A digital certificate proving trademark ownership of the logo.
A BIMI DNS record explained
A BIMI record is published in DNS and typically looks like this:
default._bimi.example.com TXT
"v=BIMI1; l=https://example.com/logo.svg; a=https://example.com/vmc.pem"
Key parameters :
v=BIMI1 is the BIMI version.
l= is the URL to the SVG logo.
a= is the URL to the VMC file (optional, but often required)
Is BIMI mandatory?
No. BIMI is optional, but increasingly valuable. Brands focused on deliverability, anti-phishing, inbox branding, and trust and recognition will benefit the most from BIMI adoption.