What are common questions and answers about BIMI email authentication?
Matthew Whittaker
Co-founder & CTO, Suped
Published 6 Jun 2025
Updated 19 Aug 2025
6 min read
Brand Indicators for Message Identification, or BIMI, is an email specification designed to display your brand's logo next to your authenticated emails in supporting inboxes. It provides a visual signal of trust and authenticity to recipients, helping them quickly identify legitimate messages from your brand. While the concept seems straightforward, implementing BIMI involves several technical considerations and common questions often arise during the process.
Many email senders are curious about how BIMI works, its prerequisites, and its actual impact on email marketing efforts and security. Understanding these common questions and their answers is crucial for a smooth implementation and to fully leverage BIMI's benefits for your brand's email presence.
BIMI is essentially a DNS TXT record that points to your brand's logo. However, it's not a standalone authentication method. It works in conjunction with robust email authentication protocols like Sender Policy Framework (SPF), DomainKeys Identified Mail (DKIM), and most importantly, DMARC. For your BIMI logo to display, your emails must first pass DMARC authentication with a policy set to either quarantine (p=quarantine) or reject (p=reject).
This strong reliance on DMARC means that BIMI acts as a reward for having a properly configured and enforced DMARC policy. It reinforces your domain's authentication posture, making it harder for phishers and spoofers to impersonate your brand. The visual presence of your logo adds another layer of trust for your recipients.
The Brand Indicators for Message Identification standard itself is maintained by the BIMI Group, an industry working group dedicated to its development and adoption. This group outlines the specifications and guidelines necessary for successful BIMI implementation and broad support across different email clients.
BIMI's fundamental requirement
BIMI requires your domain to have a DMARC policy at an enforcement level, specifically p=quarantine or p=reject. This ensures that only authenticated emails from your domain are delivered, protecting your brand's integrity and providing a secure foundation for logo display.
Implementing BIMI involves a few key requirements beyond just setting up DMARC. First, your logo must be in a specific SVG Tiny PS format. Second, for broader support, especially with major mailbox providers like Gmail and Yahoo Mail, you will need a Verified Mark Certificate (VMC).
A VMC is a digital certificate that proves your ownership of the logo and that it is trademarked. This adds an extra layer of verification, giving mailbox providers greater confidence in displaying your logo. While some providers may display BIMI without a VMC, a VMC is crucial for consistent display across the ecosystem. Information on BIMI accredited certificate providers is available to help you find a suitable issuer.
Another crucial aspect is maintaining a good sender reputation. Even with all technical configurations in place, if your domain has a poor reputation, mailbox providers might still choose not to display your logo. This means consistent adherence to email best practices, avoiding spam traps, and keeping your email lists clean are vital.
Enhanced brand recognition: Your logo appears directly in the inbox, making your emails instantly recognizable and building stronger brand recall.
Increased trust and security: The visible logo, backed by DMARC and a VMC, assures recipients the email is legitimate, reducing phishing risks.
Improved open rates: A trusted and recognizable sender is more likely to have their emails opened, potentially boosting engagement.
Challenges of BIMI
Strict prerequisites: Requires full DMARC enforcement (p=quarantine or p=reject), which can be a significant hurdle for some organizations.
Cost and complexity: Acquiring a trademark and a VMC can be costly and involve administrative effort, as detailed in our guide on BIMI implementation costs and steps.
Limited client support: Not all email clients currently support BIMI, meaning your logo won't appear everywhere.
Addressing common concerns and troubleshooting
One common concern is whether BIMI truly offers additional security or if it's merely a logo gimmick. While BIMI itself doesn't directly prevent spoofing like DMARC does, its requirement for a strong DMARC policy at an enforcement level means it inherently relies on robust authentication. This indirectly enhances security by ensuring that only legitimate emails (those that pass DMARC) are eligible for logo display, making it harder for lookalike domains to trick recipients visually.
Another frequently asked question revolves around the a= tag within the BIMI DNS record. This optional tag is designed to link to an Authority Asserted Verified Mark Certificate (AAVMC), which is a more advanced form of logo verification. Currently, the a= tag is not widely used or strictly monitored by mailbox providers, as the VMC (which links to the l= tag pointing to your SVG logo) is the primary method for verified logo display. Future plans for its stricter monitoring may emerge as the standard evolves.
For specific implementation details on displaying your logo in inboxes like GoogleGmail, our guides provide step-by-step instructions. While BIMI doesn't inherently improve your email deliverability rate, it can indirectly boost engagement due to increased brand trust and recognition. Learn more about whether BIMI improves email deliverability in our dedicated article.
I often hear questions about BIMI from various email professionals. Here are some insights from practitioners in the field.
Best practices
Ensure your DMARC policy is at p=quarantine or p=reject before attempting BIMI, as this is a non-negotiable prerequisite for logo display.
Obtain a Verified Mark Certificate (VMC) for your trademarked logo to ensure consistent display across a wider range of supporting email clients.
Maintain a strong sending reputation by adhering to email best practices, as mailbox providers use this signal alongside authentication to decide on logo display.
Convert your logo to the SVG Tiny PS format as required, ensuring it's publicly accessible via HTTPS.
Common pitfalls
Expecting immediate logo display after setting up BIMI; reputation and a proper VMC are crucial for consistent visibility.
Neglecting DMARC alignment, which is essential for BIMI to function correctly and for email authentication to pass.
Underestimating the costs and administrative effort involved in obtaining a trademark and a Verified Mark Certificate.
Confusing BIMI as a primary security mechanism; it enhances security by leveraging DMARC, but it's primarily a visual trust indicator.
Expert tips
BIMI is not a standalone security protocol, but rather a visual indicator that builds upon the security foundation provided by DMARC enforcement.
The commercial benefits of BIMI are primarily in brand recognition and trust, which can lead to increased engagement and reduced phishing susceptibility.
Mailbox providers often consider factors like sender reputation and consistent email volume when deciding whether to display a BIMI logo, even with all technical settings correct.
The 'a=' tag for Authority Asserted Verified Mark Certificates is currently optional and not widely enforced, so focus on the 'l=' tag for your SVG logo and a standard VMC.
Expert view
Expert from Email Geeks says BIMI may only work for large volume senders with an established reputation.
September 30, 2019 - Email Geeks
Marketer view
Marketer from Email Geeks says they have received conflicting information regarding whether BIMI covers commercial or transactional traffic, and clarification would be beneficial.
October 1, 2019 - Email Geeks
Elevating your brand with BIMI
BIMI offers a compelling way for brands to enhance their email presence by displaying verified logos directly in the inbox. While it requires a solid foundation of email authentication, particularly an enforced DMARC policy, the benefits in terms of brand recognition, trust, and potential engagement are significant. It’s a powerful visual component that helps your emails stand out.
Successfully navigating BIMI implementation involves understanding its technical prerequisites, securing a trademarked logo, and potentially obtaining a Verified Mark Certificate. By addressing these common questions and adhering to best practices, organizations can effectively leverage BIMI to build stronger relationships with their recipients and strengthen their overall email security posture.
Gmail and 
Yahoo Mail, you will need a Verified Mark Certificate (VMC).
GoogleGmail, our guides provide step-by-step instructions. While BIMI doesn't inherently improve your email deliverability rate, it can indirectly boost engagement due to increased brand trust and recognition. Learn more about whether BIMI improves email deliverability in our dedicated article.
