Does Yahoo Mail cache BIMI images, and how do they handle image loading?
Michael Ko
Co-founder & CEO, Suped
Published 8 Jul 2025
Updated 19 Aug 2025
7 min read
When you're working to get your brand logo displayed in inboxes, especially through Brand Indicators for Message Identification (BIMI), understanding how different mailbox providers handle images is crucial. One common question that comes up is about Yahoo Mail, specifically whether it caches BIMI images and how its image loading practices affect this process.
Yahoo Mail, like many other major webmail clients such as Gmail, has implemented image caching policies. These policies are primarily in place to protect user privacy, improve email loading times, and enhance security by preventing malicious content or unwanted tracking pixels from being loaded directly from external servers.
The caching means that when an email containing images arrives in a Yahoo Mail inbox, the images are often downloaded and stored on Yahoo's own proxy servers rather than being fetched directly from the sender's server each time the email is opened. This has significant implications for email marketers and deliverability professionals, especially concerning tracking and brand logo display.
Yahoo's general approach to image loading
Yahoo's general approach to image loading
Yahoo Mail's standard image loading practice involves serving images through its own proxy. This technique prevents external servers from gaining information about email opens, such as IP addresses or exact open times, which are typically captured when an image pixel is loaded directly from the sender's server. It's a privacy-first approach that anonymizes the user's interaction with the email content.
For regular email content images, this means that once Yahoo has cached an image, subsequent opens of that email by the same user or other users might not trigger a new request to your server. This can lead to discrepancies in open rate tracking if you rely solely on image pixel loading. Webmail providers have been doing this for years to improve user experience.
While this protects user privacy, it presents a challenge for marketers who rely on pixel-based tracking for precise open rates. The impact can be significant, potentially skewing your engagement metrics. Therefore, it's essential to understand that image caching is a fundamental part of how many major email clients, including Yahoo Mail, operate.
Impact on email tracking
Yahoo Mail's image caching, similar to Gmail's caching, means that traditional pixel-based open tracking can be inaccurate. Once an image is cached, subsequent opens may not trigger a new request to your server, leading to underreported open rates. This also means you can't reliably track IP addresses or locations of opens through images.
BIMI logos and Yahoo's caching behavior
BIMI logos and Yahoo's caching behavior
The question of whether BIMI logos are cached by Yahoo Mail is more nuanced. While Yahoo does cache standard email images, BIMI logos are retrieved differently. BIMI relies on a DNS record that points to your brand's verified SVG logo. When an email client supports BIMI, it looks up this DNS record and fetches the logo from the specified URL.
For BIMI logos, Yahoo has indicated that it will indeed add your domain name to their BIMI domain list to check for and cache your logo if needed. This means that, yes, BIMI images are cached. The caching period for BIMI logos can be influenced by the DNS Time-To-Live (TTL) value of your BIMI TXT record. If you update your BIMI logo, it might take some time for Yahoo's cache to refresh and display the new logo due to this caching.
This caching behavior is why you might sometimes see an old BIMI logo for a period after making an update, or experience delays in the new logo appearing across all Yahoo inboxes. If you are experiencing issues with your logo not appearing correctly, you can try troubleshooting it by checking our guide on how to troubleshoot BIMI logo not displaying in Yahoo Mail.
Standard image caching
For regular images embedded in email content, Yahoo caches them directly. This serves to anonymize the user, preventing external servers from knowing when an email is opened or who opened it. It also speeds up load times for subsequent opens.
This caching impacts email tracking metrics, often leading to underreported open rates. It's a measure to enhance user privacy rather than to facilitate marketing analytics.
BIMI logo caching
BIMI logos are also cached by Yahoo Mail. However, their retrieval is based on a DNS record which includes a URL to the SVG file. The DNS TTL value can influence how long the logo is cached and how quickly updates propagate.
While providing a security indicator for recipients, the caching can result in delays when updating your BIMI logo, as the new image may not appear instantly in all cached instances.
Factors influencing BIMI logo display in Yahoo
Factors influencing BIMI logo display in Yahoo
Displaying your BIMI logo in Yahoo Mail goes beyond just having a DNS record. Yahoo's systems consider several factors before deciding to show your logo. These factors are often related to sender reputation and compliance with email authentication standards.
A key requirement for BIMI is a DMARC policy set to quarantine or reject. This robust authentication ensures that only legitimate emails from your domain are delivered. Without a strong DMARC policy, your BIMI logo is unlikely to be displayed, regardless of other settings. For a deeper understanding, check out our guide on DMARC, SPF, and DKIM.
The SVG file for your logo must also adhere to specific BIMI requirements, including being a tiny-PS version and hosted securely. A Verified Mark Certificate (VMC) is also a prerequisite for BIMI adoption by Yahoo. This certificate verifies your brand's ownership of the logo and adds an extra layer of trust. You can find more details on how to get started in our article about implementing BIMI.
Must be at an enforcement policy (p=quarantine or p=reject).
Crucial for Yahoo to trust your domain and display the logo.
Verified mark certificate (VMC)
A digital certificate that verifies ownership of the trademarked logo.
Required by Yahoo for BIMI logo display to ensure authenticity.
SVG logo format
The logo must be in SVG Tiny 1.2 format, hosted securely via HTTPS.
Incorrect format will prevent the logo from rendering.
Sender reputation
Overall sending reputation with Yahoo. If your domain is on a blocklist (or blacklist), your emails will likely not reach the inbox.
A good reputation is essential for Yahoo to consider displaying your BIMI logo.
Updating BIMI logos and cache refresh
Updating BIMI logos and cache refresh
When you update your BIMI logo or any part of your BIMI DNS record, patience is key. Due to caching by providers like Yahoo, it can take time for these changes to propagate. The DNS TTL value of your BIMI TXT record plays a role here; a lower TTL might lead to faster updates, but it also increases DNS query load. However, even with a low TTL, Yahoo’s internal caching mechanisms might have their own refresh cycles.
If you're noticing that your BIMI logo isn't updating as quickly as you'd like in Yahoo Mail, it's typically a caching issue. It's not always an immediate refresh. Ensuring your DMARC is correctly configured and your SVG file is valid are the primary steps, but then it's a waiting game for the caches to update. Why isn't my BIMI logo showing up in Yahoo provides additional troubleshooting steps.
Views from the trenches
Best practices
Ensure your DMARC policy is set to p=quarantine or p=reject for BIMI to work effectively.
Always use a validated SVG Tiny 1.2 format for your BIMI logo and host it over HTTPS.
Obtain a Verified Mark Certificate (VMC) for your trademarked logo to satisfy Yahoo's requirements.
Common pitfalls
Setting a low DNS TTL for BIMI records expecting instant updates; Yahoo still has its own cache.
Not having a strong DMARC policy in place, which is a fundamental requirement for BIMI support.
Using an SVG file that doesn't meet the specific BIMI SVG Tiny 1.2 format, causing display errors.
Expert tips
BIMI logos are subject to caching by email providers like Yahoo, influenced by DNS TTL and internal refresh cycles.
Yahoo's image caching, for both regular and BIMI images, is designed to protect user privacy and prevent tracking.
If your BIMI logo isn't appearing, verify DMARC policy, SVG format, and VMC, then allow time for caching to clear.
Marketer view
Marketer from Email Geeks says that BIMI logos did not appear to be cached because previous emails updated with the new logo after implementation.
2019-10-29 - Email Geeks
Expert view
Expert from Email Geeks says Yahoo likely caches BIMI logos for a specific period, though the exact duration varies as different domains implement BIMI differently.
2019-10-29 - Email Geeks
Key takeaways
Key takeaways
In summary, Yahoo Mail does cache both general email images and BIMI logos, primarily through its own proxy servers. This practice is integral to its privacy and performance strategies. For standard images, caching helps protect user privacy by obscuring direct interaction with external servers, impacting open rate tracking.
For BIMI logos, while cached, their display is contingent on rigorous authentication, including a strong DMARC policy, a valid VMC, and correctly formatted SVG files. Understanding these caching behaviors and authentication requirements is essential for ensuring your brand logo is consistently and accurately displayed in Yahoo Mail inboxes.
Gmail's caching, means that traditional pixel-based open tracking can be inaccurate. Once an image is cached, subsequent opens may not trigger a new request to your server, leading to underreported open rates. This also means you can't reliably track IP addresses or locations of opens through images.
DMARC policy
Verified mark certificate (VMC)
