Why am I seeing open rate drops specifically in California?
Matthew Whittaker
Co-founder & CTO, Suped
Published 30 Jun 2025
Updated 13 Oct 2025
7 min read
Experiencing a sudden dip in email open rates can be concerning, but it's even more perplexing when that drop is isolated to a specific geographic region, like California. It's a common scenario where everything seems consistent, yet your metrics in one state are telling a different story, especially during certain days of the week.
The challenge often lies in understanding how major email service providers and geolocation services interact. This localized drop isn't necessarily a sign that Californians are suddenly disengaging from your content, but rather a potential indicator of how email platforms handle metrics and the complex world of email deliverability.
The impact of geolocation and email client behavior
One of the primary reasons for a localized drop in open rates, particularly in California, often ties back to Google's email infrastructure. Gmail, a dominant email provider, has its headquarters in California. While their servers are globally distributed, some geolocation databases may attribute traffic coming from Google's various data centers, including those that pre-fetch email pixels, back to their California base. This can create a false impression of activity localized to the state.
Email clients, especially on mobile devices or through privacy features like Apple Mail Privacy Protection (MPP), often pre-fetch images in emails before the recipient actually opens the message. This action is designed to enhance user experience by making emails load faster, but it can artificially inflate open rates. When a deliverability issue causes a drop in these pre-fetched pixels for a major provider like Gmail, it might appear as a significant open rate decline.
Geolocation inaccuracies
It's important to recognize that geolocation data isn't always precise. Services, even reputable ones used by email platforms, can misattribute the physical location of servers. For instance, Apple MPP's image loads, regardless of the user's actual location, might be geolocated to a specific proxy server location, such as a pond in Dublin. This illustrates how perceived regional drops can be a result of technical routing rather than user behavior. This makes it crucial to properly understand your email deliverability rate.
If your Gmail open rate is much lower on the days you're seeing overall drops in California, it strongly suggests a Google-related issue. This could be due to a temporary reputation dip, changes in how Google processes incoming mail, or adjustments to their image pre-fetching mechanisms. It's not necessarily a problem with your content, but rather with how a major provider is interacting with your sending infrastructure.
Understanding email open rate metrics
Email open rates have always been a somewhat imperfect metric, and recent privacy enhancements have only amplified their limitations. An "open" is typically tracked by a tiny, invisible pixel image loaded when the email is viewed. If that pixel isn't loaded, either because images are blocked, a user previewed the email without full rendering, or a service pre-fetched it, the open may or may not be recorded accurately. For more detail, you can read about open rate limitations.
The key takeaway is that not all recorded opens represent genuine human engagement. Opens generated by pre-fetching are not a direct indication of a user's interest in your email. If a drop in your California open rates is primarily due to a reduction in pre-fetching, it's not necessarily a bad thing for your campaign's true engagement. In fact, it might lead to a more accurate understanding of your audience.
Traditional open rate
Based on image pixel loading. Susceptible to pre-fetching and privacy features, leading to potentially inflated or inaccurate numbers.
Misleading metrics: Doesn't always reflect actual human interaction or interest.
Geolocation errors: Image loads from servers can be attributed to incorrect regions.
True engagement
Focuses on meaningful interactions like clicks, conversions, and replies. Provides a clearer picture of content impact and audience interest.
Actionable insights: Directly correlates with user interest and campaign goals.
Deliverability indicators: A drop in these metrics often points to genuine inbox placement issues.
To truly gauge your email campaign's health, you need to look beyond mere opens. Focus on metrics like click-through rates, conversions, and reply rates. These offer a more reliable indication of how engaged your audience is. If these metrics also show a significant decline alongside open rates in California, then you have a more pressing deliverability concern.
Deliverability factors and regional impact
While geolocation and pre-fetching play a role, a localized drop in open rates can also hint at underlying deliverability issues that might be more pronounced for certain ISPs or in specific regions. Major ISPs like Gmail have stringent filtering mechanisms, which can sometimes lead to regional discrepancies in inbox placement.
Your sender reputation with ISPs is crucial. Factors like spam complaints, bounce rates, and engagement levels all contribute to this score. A sudden spike in complaints from a particular region, or a perceived dip in engagement by an ISP, can trigger stricter filtering for your emails in that area. This can result in more emails landing in spam folders or being blocked entirely, directly impacting your measured open rates.
Email authentication protocols like SPF, DKIM, and DMARC are fundamental to ensuring your emails reach the inbox. If there are misconfigurations or failures in these records, ISPs may view your emails with suspicion. While issues with DMARC, SPF, and DKIM typically affect all recipients, specific regional ISPs or networks might have stricter enforcement, leading to a more pronounced impact in certain areas. For example, some regional networks might use their own local blocklists (blacklists) that could affect deliverability in specific locales.
Are you on a blocklist?
Being listed on an email blocklist (blacklist) can severely impact your deliverability. While some blocklists are global, others might be regional or specific to certain ISPs. If you find your IPs or domains on a blocklist, it's critical to take immediate action to address the issue and request removal. You can monitor your domains and IPs with Suped blocklist monitoring.
Diagnosing and improving your email deliverability
When facing a localized open rate drop, especially in a state like California, a systematic approach to diagnosis is key. Start by leveraging powerful monitoring tools. Suped's DMARC monitoring offers detailed insights into your email authentication status and deliverability, helping you pinpoint potential issues related to DMARC, SPF, and DKIM alignment. This is often the first place to look for subtle authentication problems that could impact deliverability.
Next, analyze your click-through rates and other engagement metrics for your California audience. If these metrics remain stable while open rates drop, it reinforces the idea that the issue is likely related to pixel pre-fetching rather than a lack of interest. However, if clicks and conversions are also down, it indicates a more serious inbox placement or engagement problem. You might want to troubleshoot a sudden drop in open rates.
Consider the quality of your email list for the California segment. Have you recently acquired new subscribers? Are they highly engaged? A segment with a higher proportion of inactive or unengaged subscribers can drag down overall open rates, even if your deliverability is otherwise sound. Regular list hygiene is essential for maintaining good sender reputation and optimizing performance. You can also leverage a free online email testing tool.
Finally, review any recent changes to your sending infrastructure, email content, or sending frequency that might be contributing to the issue. Even minor adjustments can sometimes trigger changes in how ISPs handle your mail. For more information, explore common reasons open rates decline.
Views from the trenches
Best practices
Actively monitor DMARC reports to spot authentication failures that might affect deliverability, especially with major providers.
Segment email performance data by recipient domain to identify specific ISP-related issues contributing to localized drops.
Focus on engagement metrics like clicks and conversions rather than just open rates to understand true audience interest.
Regularly clean and validate your email lists to maintain high sender reputation and prevent sending to inactive accounts.
Common pitfalls
Over-relying on geolocation data without considering how email clients and ISPs handle image pre-fetching.
Assuming uniform deliverability across all geographic regions, ignoring potential localized filtering rules or ISP behaviors.
Neglecting email authentication (SPF, DKIM, DMARC), which is fundamental for inbox placement across all providers.
Not cross-referencing open rate drops with other engagement metrics, leading to misinterpretations of deliverability health.
Expert tips
Utilize Google Postmaster Tools for Gmail-specific insights into spam rates and domain reputation.
Implement a DMARC policy with reporting to gain visibility into your email ecosystem and authentication results. Suped is an excellent solution.
Conduct A/B tests on subject lines and content, targeting segments experiencing drops, to identify engagement drivers.
Be aware that privacy features like Apple MPP can skew open rates, so adjust your success metrics accordingly.
Expert view
Expert from Email Geeks says that delivery problems at Google can lead to a drop in Google's pre-fetching pixels, which often results in inaccurately lowered reported open rates.
July 30, 2022 - Email Geeks
Expert view
Expert from Email Geeks mentioned that geolocation databases might misattribute locations for large companies, explaining why Google's pre-fetching could appear concentrated in California.
July 30, 2022 - Email Geeks
Navigating localized open rate challenges
Drops in open rates, particularly when localized to regions like California, can be frustrating, but they often point to a combination of technical factors and evolving email client behaviors. By understanding the role of geolocation inaccuracies, pre-fetching pixels, and the stringent filtering of major ISPs like Gmail, you can better interpret your metrics.
The key is to move beyond a sole reliance on open rates and focus on deeper engagement metrics. Implementing robust email authentication with tools like DMARC monitoring from Suped, maintaining excellent sender reputation, and regularly cleaning your email lists will provide a more stable foundation for your email marketing efforts, regardless of geographic fluctuations.
