Guides BIMI
What is BIMI?
With BIMI your logo can appear next to your emails in the inbox. It requires a strict DMARC policy. What you need for it, and what a VMC is.
BIMI (Brand Indicators for Message Identification) lets a domain owner publish a brand logo that a supporting mailbox provider may show with messages. BIMI builds on DMARC, but a correct DNS record does not guarantee that a provider retrieves or displays the logo.
How it works
You publish a TXT record at default._bimi.<domain> with an HTTPS address for a supported logo format. A provider then evaluates each message using DMARC, its own policy and, where supported, evidence from a= before displaying a logo.
BIMI does not stop lookalike domains or copied logos. DMARC can prevent a message spoofing the exact protected From domain from qualifying for BIMI.
What you need for it
- Strong DMARC policy under the BIMI draft, at both the sender and organizational domain
- Exactly one usable BIMI Assertion Record for the selector in use
- An HTTPS address in
l=for a supported logo format - Optional evidence in
a=, when the receiving provider supports or requires it
Evidence and provider policy
The optional a= tag can point to a BIMI Evidence Document. The BIMI draft leaves support and validation to the receiver and to separate document profiles. Providers may also impose their own requirements, such as a particular kind of mark certificate. Check the current documentation of the provider you want to support; DNS alone cannot prove that an evidence document is valid or accepted.
Why you'd want this
BIMI does not make a message authentic by itself. The security boundary is SPF, DKIM, DMARC and receiver policy. BIMI can add recognition when a provider chooses to display the logo. Treat it as presentation, not as a universal security badge.
Primary sources
Frequently asked questions
Do I need DMARC for BIMI?
Yes. The BIMI draft requires strong DMARC policy at both the sender domain and the organizational domain. p=none does not pass that protocol gate.
Do I always need a VMC?
Not as a universal protocol rule. Evidence-document support and extra certificate requirements differ by provider and can change. Check the provider's current documentation.
What logo format should I use?
The current draft names SVG and SVGZ and points to separate profiles for further restrictions. The DNS scan checks only the published address, not the retrieved file contents. Check the current BIMI profile and your provider's requirements.
Does BIMI improve my deliverability?
Not directly. BIMI is mainly about visibility and trust. The deliverability gain comes from the SPF/DKIM/DMARC you need for it anyway.