BIMI (Brand Indicators for Message Identification) shows your logo next to your emails in supporting inboxes. Since September 2024 Gmail also accepts Common Mark Certificates (CMCs), which need no registered trademark. BIMI does not decide inbox or spam placement, Outlook does not support it, and a mark certificate costs hundreds of dollars a year per domain, so for rotating cold email domains it is rarely worth it. Get authentication, warming, lists and copy right first, and consider BIMI only for a primary brand domain.
Some senders show a brand logo next to their name in Gmail, Apple Mail and Yahoo. That is BIMI. For years it required a registered trademark, which kept most cold email teams out. Gmail relaxed that in September 2024.
This guide covers what BIMI is, what Common Mark Certificates changed, what it costs, and whether it is worth setting up for cold email in 2026.
What Is BIMI?
BIMI stands for Brand Indicators for Message Identification. It is an email standard that lets a supporting inbox show your logo next to your message instead of a generic initial or avatar.
According to the BIMI Group's support list (checked October 2026), mailbox providers that support BIMI include:
- Gmail: accepts both Verified Mark Certificates (VMCs) and Common Mark Certificates (CMCs).
- Apple Mail: iOS 16, iPadOS 16, macOS Ventura 13 or later and iCloud.com, using VMCs (Apple's BIMI support page does not list CMCs).
- Yahoo Mail, Fastmail, Zoho Mail and several regional providers.
One notable absence: Microsoft Outlook does not support BIMI, per the same BIMI Group list. If many of your prospects use Outlook or Microsoft 365, BIMI has no visual effect for them.
BIMI is not an authentication protocol. It is a display layer that sits on top of SPF, DKIM and DMARC.
How BIMI Works
BIMI works through a chain of requirements. Each one must be in place before your logo will display:
- Enforced DMARC policy: your domain's DMARC record must be
p=quarantineorp=reject.p=noneis not enough. - Aligned authentication: messages must pass SPF or DKIM with a domain that aligns with your From address.
- SVG logo file: the logo must be in SVG Tiny Portable/Secure (SVG P/S) format, a restricted subset of SVG. A standard SVG export will not work.
- Mark certificate: a Verified Mark Certificate (VMC) or a Common Mark Certificate (CMC) that ties your logo to your domain.
- BIMI DNS record: a TXT record at
default._bimi.yourdomain.comthat points to your hosted logo and certificate.
The receiving server checks your DMARC policy, confirms authentication passed, looks up the BIMI record, validates the certificate and then shows the logo. The recipient does nothing.
Common Mark Certificates
Before September 2024, Gmail only accepted VMCs, and a VMC requires a registered trademark. On September 24, 2024 Google announced that Gmail also accepts Common Mark Certificates. The differences:
- No trademark required: instead, certificate authorities require the logo to have been in documented public use for at least 12 months.
- No blue checkmark: Google's announcement says a CMC shows the brand avatar "without the Gmail verified checkmark that's displayed for VMCs."
- Narrower support: Apple Mail still lists only VMCs.
- Still not cheap: as of October 2026, one DigiCert reseller (SSL Dragon) lists a DigiCert CMC at $949 per year and a VMC at $1,249 per year. Prices vary by certificate authority and reseller.
CMCs removed the trademark barrier, not the cost barrier.
BIMI's Impact on Cold Email
Potential Benefits
- A recognizable logo: a logo stands out next to generic initials and can make a message look more legitimate to the recipient.
- Signals a real sender: BIMI requires DMARC enforcement, so a spoofer cannot borrow your logo on your domain.
- Brand familiarity: prospects who see the same logo across a sequence may recognize you on later touches.
We are not aware of a reliable, published study of BIMI's effect on cold email open or reply rates, and open tracking itself has become unreliable, so treat any claimed lift with caution.
Limitations
- No direct deliverability improvement: BIMI does not decide whether a message lands in the inbox or spam. Authentication, domain and IP reputation, list quality and content do.
- Limited coverage: no logo for Outlook or Microsoft 365 recipients, and no logo in Apple Mail with a CMC.
- Requires DMARC enforcement: you need
p=quarantineorp=reject, which you should have on cold email domains anyway. - Per-domain cost: cold email spreads volume across many secondary domains. A certificate for each one at the prices above costs far more than the domains and mailboxes themselves.
- A brand logo on a secondary domain: putting your company logo on outreach domains links them visibly to your brand, which cuts against keeping them separate from your main domain.
The Honest Assessment
If your deliverability is already good, BIMI adds a trust signal on your main brand domain. If your deliverability is poor (spam placement, authentication failures, low replies), BIMI fixes none of it.
How to Set Up BIMI
If you decide BIMI is worth it for a domain, the steps are:
Step 1: Ensure DMARC Is Enforced
Check your DMARC record. It must be p=quarantine or p=reject. Domains you buy through Winnr get a p=reject DMARC policy automatically (DNS health help). Verify with:
dig TXT _dmarc.yourdomain.com
You should see something like v=DMARC1; p=quarantine; rua=mailto:dmarc@yourdomain.com or p=reject.
Step 2: Create Your SVG Logo
Your logo must be in SVG Tiny Portable/Secure (SVG P/S) format. The main requirements:
- Square aspect ratio
- Logo centered on a solid background
- No animation, no scripts, no external references
- SVG Tiny 1.2 profile
- Small file size (the BIMI Group recommends keeping it under 32KB)
Several online tools convert a standard SVG to SVG P/S. If you have a designer, give them the BIMI SVG specification.
Step 3: Obtain a CMC or VMC
If you do not have a registered trademark, a CMC is the only option, and it shows in Gmail but not Apple Mail. With a trademark, a VMC covers both. DigiCert is one certificate authority that issues both. You will verify domain control and submit your logo and evidence of its use.
Step 4: Host Your Logo and Certificate
Upload the SVG logo and the PEM certificate to a public HTTPS URL. For example:
https://yourdomain.com/bimi/logo.svghttps://yourdomain.com/bimi/cert.pem
Step 5: Add the BIMI DNS Record
Create a TXT record at default._bimi.yourdomain.com with this value:
v=BIMI1; l=https://yourdomain.com/bimi/logo.svg; a=https://yourdomain.com/bimi/cert.pem
On domains where Winnr hosts DNS, you can add this TXT record yourself from the domain's DNS Records tab (see custom DNS records).
Step 6: Verify
Use the BIMI Group's inspector to check your DMARC record, BIMI record, logo format and certificate. Fix anything it reports before you consider the setup done.
Cost-Benefit Analysis for Cold Email
| Item | Cost | Benefit |
|---|---|---|
| Mark certificate (CMC or VMC) | Hundreds of dollars or more per year, per certificate (example DigiCert reseller prices above, October 2026) | Logo in Gmail (CMC); Gmail and Apple Mail (VMC) |
| SVG P/S logo | Your time or a designer's, if you already have a logo | Correctly formatted logo |
| DNS record | No cost, a few minutes | Points receivers to logo and certificate |
| DMARC enforcement | No cost (should already be in place) | Required anyway for cold email domains |
For a company sending from one or two brand domains, the certificate can be justified as a branding expense. For a cold email setup spread across many secondary cold email domains, certifying every domain is rarely sensible. Spend that budget on more domains, mailboxes and list quality instead.
Our Recommendation
BIMI belongs at the end of your deliverability list, not the start. The order that matters:
- SPF, DKIM and DMARC: on every domain, every time.
- Warming: build sending history before you scale volume.
- Content and list quality: relevant emails to verified contacts.
- Sending practices: 10 to 20 cold emails per mailbox per day, about 50 in total including warming, sent consistently.
- BIMI: only once 1 to 4 are solid, and usually only on your primary brand domain.
If you are still working on the first four, BIMI should wait.
Related guides: Set up your domains correctly with our DNS setup checklist, read why Winnr uses DMARC p=reject by default, or review the cold email best practices guide.
Frequently Asked Questions
Does BIMI improve email deliverability?
No. BIMI is a display standard. It decides whether your logo appears next to your email in supporting inboxes, not whether the email reaches the inbox. Placement is driven by authentication (SPF, DKIM, DMARC), domain and IP reputation, list quality and content. BIMI does require DMARC enforcement, which is good practice anyway.
Is BIMI worth it for cold email?
Usually not on secondary sending domains. A mark certificate costs hundreds of dollars a year per certificate (a DigiCert CMC was listed at $949 a year by one reseller in October 2026), Outlook shows no BIMI logos, and BIMI does not affect inbox placement. It can make sense on a primary brand domain once your authentication, warming, lists and copy are already in good shape.
Does Outlook support BIMI?
No. As of October 2026 the BIMI Group lists Microsoft Outlook as not supporting BIMI, so logos do not display for Outlook, Outlook.com or Microsoft 365 recipients. BIMI logos display in Gmail, Apple Mail (with a VMC), Yahoo Mail, Fastmail and other supporting providers.