Email Security8 min read

How to Setup BIMI: Brand Indicators for Message Identification

BIMI displays your brand logo next to emails in supported mail clients. Setting it up requires DMARC enforcement, a BIMI-compliant SVG logo, and optionally a Verified Mark Certificate.

BIMI (Brand Indicators for Message Identification) is an email standard that displays your company logo directly in the recipient's inbox next to authenticated emails. It builds trust with recipients and helps your emails stand out. Setting up BIMI requires meeting strict prerequisites — this guide walks through every step.

BIMI Prerequisites

Before you can implement BIMI, you must have:

  • DMARC at enforcement: Your DMARC policy must be p=quarantine or p=reject. BIMI does not work with p=none.
  • SPF and DKIM configured: Both must pass for the emails that will display the logo.
  • A domain-owned BIMI-compliant SVG logo: A specific SVG format is required.
  • (Optional but required for Gmail) A Verified Mark Certificate (VMC): Issued by a qualified CA, proving trademark ownership.
VMC for GmailGmail requires a Verified Mark Certificate (VMC) to display BIMI logos. Apple Mail, Yahoo Mail, and Fastmail support BIMI logos without a VMC. If Gmail is your primary target, budget for VMC costs ($1,000–$1,500/year from DigiCert or Entrust).

Step 1: Confirm DMARC Enforcement

Check your current DMARC policy:

bash
dig _dmarc.yourdomain.com TXT +short # Must show p=quarantine or p=reject

Or use the ShowDNS DMARC Lookup tool. If your policy is p=none, move to p=quarantine or p=reject before proceeding. See the DMARC configuration guide for steps.

Step 2: Prepare Your BIMI Logo

BIMI requires a very specific SVG format called SVG Tiny 1.2. Your logo must:

  • Be in SVG Tiny 1.2 format (not standard SVG 1.1).
  • Have a square aspect ratio.
  • Have no external resource links (fonts, images).
  • Use only supported SVG features (no filters, scripts, or animations).
  • Be self-contained — all paths and colors embedded in the file.
  • Typically be between 10KB and 32KB in size.
xml
<?xml version="1.0" encoding="UTF-8"?> <svg xmlns="http://www.w3.org/2000/svg" version="1.2" baseProfile="tiny" viewBox="0 0 100 100"> <!-- Your logo paths here — no external resources --> <circle cx="50" cy="50" r="40" fill="#0066cc"/> <text x="50" y="65" text-anchor="middle" fill="white" font-size="40">AB</text> </svg>

Use an SVG validator or the BIMI group's SVG checker at bimigroup.org to confirm compliance. Many design tools (Illustrator, Inkscape) do not export SVG Tiny 1.2 directly — manual cleanup of the SVG is usually needed.

Step 3: Host Your Logo

The SVG logo must be hosted at a publicly accessible HTTPS URL. Host it on your own domain for maximum control:

text
# Example hosting location https://example.com/bimi/logo.svg # Or a standard location https://example.com/.well-known/bimi/logo.svg

Verify the URL is accessible and returns the correct SVG content type (image/svg+xml).

Step 4: (Optional) Obtain a Verified Mark Certificate (VMC)

For Gmail support, you need a VMC from a qualified CA. Currently, VMCs are issued by:

  • DigiCert (digicert.com/verified-mark-certificates)
  • Entrust (entrust.com/email-security)

The VMC process requires:

  1. A registered trademark for your logo in the countries you want covered.
  2. Trademark documentation submitted to the CA.
  3. CA validation (takes days to weeks).
  4. The CA issues a VMC file (a .pem certificate) that links your trademark to your SVG logo.

Host the VMC file at an HTTPS URL (the CA provides download instructions).

Step 5: Publish the BIMI DNS Record

The BIMI record is a TXT record published at a specific subdomain: default._bimi.yourdomain.com.

Without a VMC (Yahoo, Apple Mail, Fastmail)

text
# DNS record Record type: TXT Name: default._bimi.yourdomain.com Value: "v=BIMI1; l=https://example.com/bimi/logo.svg;"

With a VMC (Gmail + others)

text
# DNS record with VMC Record type: TXT Name: default._bimi.yourdomain.com Value: "v=BIMI1; l=https://example.com/bimi/logo.svg; a=https://example.com/bimi/vmc.pem"

The BIMI record tags:

  • v=BIMI1 — BIMI version identifier (required).
  • l= — URL of the BIMI-compliant SVG logo (required).
  • a= — URL of the VMC certificate (required for Gmail).

Step 6: Verify Your BIMI Setup

Check that the BIMI record is published correctly:

bash
# Verify BIMI DNS record dig default._bimi.yourdomain.com TXT +short # Expected: "v=BIMI1; l=https://example.com/bimi/logo.svg; a=https://example.com/bimi/vmc.pem"

Use the ShowDNS BIMI Lookup tool to verify the record and check whether the logo URL is accessible.

To test in Gmail, send an email from your domain to a Gmail address and check whether the logo appears. Note that Gmail may take time to process BIMI for a domain — it is not instant.

BIMI for Subdomains

BIMI records can be configured per subdomain or use the parent domain's record. For email sent from mail.example.com:

text
# Subdomain-specific BIMI record default._bimi.mail.example.com TXT "v=BIMI1; l=https://example.com/bimi/logo.svg;"

If no subdomain record exists, mail clients fall back to the organizational domain's (example.com) BIMI record.

Frequently Asked Questions

Does BIMI improve email deliverability?

BIMI requires DMARC enforcement, which is the primary deliverability benefit. The logo itself is a trust signal for recipients but does not directly affect spam filtering scores. The DMARC enforcement required for BIMI does improve deliverability.

Which email clients support BIMI?

Gmail (with VMC), Apple Mail, Yahoo Mail, Fastmail, and Proton Mail support BIMI. Outlook does not currently support BIMI. Check the BIMI group's website for the current list of supporting clients.

How long does it take for BIMI to show up?

DNS propagation is typically fast (minutes to hours). Gmail may take days or weeks to recognize and display a new BIMI setup. Yahoo and Apple Mail are generally faster. Send test emails and check after 24–48 hours.

Can I use a PNG logo for BIMI?

No. BIMI strictly requires SVG Tiny 1.2 format. PNG, JPG, and standard SVG 1.1 are not accepted.

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