BIMI stands for Brand Indicators for Message Identification. It is an email standard that allows organizations to display their trademarked brand logos next to authenticated email messages in recipient inboxes, provided they have a strict DMARC policy in place.

Is a VMC (Verified Mark Certificate) always required for BIMI?

No, a Verified Mark Certificate (VMC) is not always required. While Gmail and Apple Mail mandate a VMC for BIMI logo display, Yahoo Mail (and AOL ) currently support BIMI without a VMC. Your logo must be a registered trademark to obtain a VMC.

What are the technical requirements for the BIMI logo file?

Your BIMI logo must be in SVG Tiny 1.2 format, square, and served over HTTPS. It should not exceed a certain file size (typically 32KB). For providers requiring a VMC, the logo must also be a registered trademark.

What email authentication protocols are required for BIMI?

To enable BIMI, you must have SPF, DKIM, and DMARC correctly configured for your sending domain. Crucially, your DMARC policy must be at an enforcement level, specifically "p=quarantine" or "p=reject", meaning it actively quarantines or rejects unauthenticated emails.

Which email providers currently support BIMI?

Major email providers currently supporting BIMI include Gmail , Yahoo Mail (including AOL), and Apple Mail. Each may have slightly different requirements, particularly regarding the VMC.

What are the requirements to implement BIMI, and which providers support it? - Technical - Email deliverability - Knowledge base

As email deliverability becomes increasingly critical, new standards like Brand Indicators for Message Identification (BIMI) are emerging to help brands stand out and build trust. BIMI allows your brand's logo to appear next to your sender name in supported inboxes, providing a visual confirmation of your identity to recipients. This not only enhances brand recognition but also helps prevent phishing attacks by making it harder for imposters to mimic your brand.

However, implementing BIMI isn't as simple as just uploading a logo. There are specific technical requirements and different levels of support from various mailbox providers. Understanding these prerequisites is key to a successful deployment and ensuring your logo is displayed consistently across the email ecosystem.

Authenticating your domain with SPF, DKIM, and DMARC

Before you can even think about BIMI, your domain needs to have a robust email authentication foundation. This means properly configuring SPF, DKIM, and DMARC. These three protocols work together to verify that your emails are legitimately from your domain and haven't been tampered with in transit. Without them, your emails are more likely to land in the spam folder, making BIMI irrelevant.

Specifically, DMARC is a non-negotiable requirement for BIMI. Your DMARC policy must be set to either "quarantine" or "reject" (p=quarantine or p=reject), ensuring that emails failing authentication are either moved to spam or blocked entirely. A policy of "none" (p=none), while useful for monitoring, will not satisfy the BIMI requirements. This strict DMARC enforcement is crucial for establishing the necessary level of trust with mailbox providers, enabling them to confidently display your logo.

This strong authentication framework protects your brand and recipients from impersonation and phishing. For a more detailed look at these essential protocols, consider reviewing our guide on a simple guide to DMARC, SPF, and DKIM.

DMARC enforcement is key

BIMI mandates that your DMARC policy is actively enforcing, meaning it must be set to either quarantine or reject. This commitment to email security signals to mailbox providers that your sending domain is well-protected against unauthorized use.

Transitioning to a strict DMARC policy should be done carefully, ideally with comprehensive DMARC monitoring in place to avoid legitimate emails being blocked. You can find more information about this transition in our guide on how to safely transition your DMARC policy.

Preparing your BIMI logo

Once your email authentication is strong, the next step for BIMI is your brand logo itself. This isn't just any image, though, it has specific technical requirements. The logo must be a square-shaped Scalable Vector Graphics (SVG) file, specifically in the SVG Tiny 1.2 format. It also needs to be publicly accessible via HTTPS. You'll specify the URL to this SVG file in your BIMI DNS record.

The SVG file requires precise formatting to be compatible with BIMI. Incorrect SVG formatting is a common reason for BIMI implementation failures. For detailed instructions on how to prepare your logo, refer to the BIMI Group's guide on creating SVG logo files. Additionally, we have a resource on BIMI SVG file requirements and validation.

Trademarked logo (required by some providers)

For some prominent mailbox providers, such as

Gmail and

Apple Mail, your logo must be a registered trademark. This is a critical step because it allows you to obtain a Verified Mark Certificate (VMC).

Obtaining a Verified Mark Certificate (VMC)

A Verified Mark Certificate (VMC) is a digital certificate that verifies the authenticity of your trademarked logo and your ownership of the domain. It acts as an additional layer of trust, ensuring that only legitimate brands can display their logos. While not all BIMI-supporting providers require a VMC, it is mandatory for significant players like

Google and

Apple. Obtaining a VMC involves a rigorous validation process by a Certificate Authority (CA).

The process of getting a VMC typically involves verifying your domain ownership, proving your organization's legal existence, and, most importantly, demonstrating that your logo is a registered trademark with an intellectual property office. This process can be time-consuming and involves a financial investment. Approved Certificate Authorities for BIMI include DigiCert and Entrust. Our guide on BIMI accredited certificate providers can offer more insights.

Once you have your VMC, you'll need to link it in your BIMI DNS record, alongside the SVG logo URL. This completes the technical setup for providers that require a VMC, allowing them to fetch and display your verified brand logo. For more information, you can check Google's support documentation on setting up BIMI for Google Workspace.

Mailbox provider support and VMC requirements

BIMI adoption among mailbox providers is growing, but support and specific requirements can vary. Currently, the most prominent providers that officially support BIMI are

Yahoo Mail (including

AOL),

Gmail, and

Apple Mail. Other providers might be running trials or considering implementation.

The key distinction lies in the VMC requirement.

Yahoo (and

AOL) currently supports BIMI without requiring a VMC. This means you can display your logo in these inboxes if your authentication (SPF, DKIM, DMARC) and SVG logo are correctly configured. However,

Gmail and

Apple Mail mandate a VMC for logo display. This distinction is crucial for planning your BIMI implementation strategy. For more details on this, see our article on which email providers support BIMI without a VMC.

The table below provides a summary of major mailbox providers and their current BIMI support and VMC requirements.

Mailbox Provider	BIMI Support	VMC Requirement
Gmail	Full support	Required
Yahoo Mail / AOL	Full support	Not required
Apple Mail	Full support	Required

Implementing BIMI requires careful attention to detail, from your DMARC policy to your SVG logo file. Meeting these requirements ensures your brand logo appears consistently, boosting trust and brand recognition. For more specific instructions on implementing BIMI for Gmail and Yahoo, consult our detailed guides.

Views from the trenches

Best practices

Ensure your DMARC policy is at p=quarantine or p=reject before initiating BIMI setup.

Verify your SVG logo file meets all technical specifications, including SVG Tiny 1.2 format and HTTPS hosting, using available validation tools.

For VMC-requiring providers, confirm your logo is a registered trademark before starting the certificate application process.

Common pitfalls

Attempting BIMI implementation without a DMARC policy at enforcement, leading to non-display.

Using an improperly formatted SVG logo, which can cause display issues or outright rejection by mailbox providers.

Expecting BIMI logos to appear across all providers without accounting for VMC requirements or individual provider support policies.

Expert tips

Consider using a subdomain for your BIMI record if you have multiple brands or wish to perform A/B testing on logos.

Monitor your DMARC reports closely during and after BIMI implementation to catch any authentication failures.

Stay updated on mailbox provider policies, as BIMI support and requirements can evolve over time.

Marketer view

Marketer from Email Geeks says they confirmed that the SVG image format needs to be SVG Tiny 1.2 for BIMI implementation, not SVG P/S.

2020-12-14 - Email Geeks

Expert view

Expert from Email Geeks says that for a logo to be shown on Gmail (Google Pilot), an invitation to the pilot program, a valid VMC, and a registered logo mark are all necessary, with VMCs currently available only to US-based organizations.

2020-12-15 - Email Geeks

Final thoughts on BIMI implementation

Implementing BIMI involves more than just publishing a DNS record. It requires a solid foundation of email authentication, including SPF, DKIM, and a DMARC policy enforced at quarantine or reject. Beyond that, your brand logo must meet strict technical specifications as an SVG file, and for many major mailbox providers, it needs to be a registered trademark, leading to the necessity of a Verified Mark Certificate (VMC).

While the process can seem complex, the benefits of BIMI, such as enhanced brand visibility and increased trust, make it a worthwhile investment for any brand serious about its email deliverability and reputation. By carefully adhering to these requirements, you can successfully implement BIMI and display your logo proudly in inboxes worldwide.