The June 2025 Core Update's Hidden Impact

Reading time: 9 minutes. Updated: 19th September 2025.

This analysis was originally published focusing solely on the June 2025 Core Update and its impact, comparing June 2025 data with August 2025 data.

However, Google's actions in September 2025 - including the ongoing August 2025 Spam Update and changes to search result accessibility - have added important context to these regional findings.

The situation remains fluid, with Google yet to make any official announcement about the changes or their implications for search data reporting. The update that follows examines these developments and reviews September 2025 data in relation to the original analysis.

Original Article:

In July, I observed huge boosts in Google organic search impressions in Australian search results, corresponding with the June 2025 Core Update.

Much of the industry commentary around the June 2025 Core Update has been decidedly USA-centric, with the usual discussion of winners, losers, and ranking volatility. What I haven't seen is much analysis of how this update impacted specific regional markets.

So, I analysed Google Search Console data across multiple websites - including both Australian businesses and international companies - targeting Australian consumers with their products and services. The analysis revealed something remarkable: the difference between global and Australian-filtered performance data told completely different stories.

This article brings those findings together to highlight how regional variations can be masked by aggregate data, and what the Australian experience might signal about Google's evolving approach to search results.

Three key takeaways:

• Regional Data Reveals Hidden Opportunities: Australian-filtered search results showed dramatically different performance patterns compared to global data during the June 2025 Core Update. Websites targeting Australian audiences experienced impression gains of 118-224%*, whilst their global performance appeared modest. This highlights how aggregate data can mask significant regional variations and opportunities.
• Google's AI Systems Increasingly Value Geographic Context: The dramatic gains for websites with strong local signals suggest that Google's shift towards AI-driven content evaluation particularly rewards clear geographic relevance, from technical implementation to content localisation.
• Search Visibility Evolution Requires Metric Reframing: The consistent pattern of soaring impressions alongside declining CTRs represents the new normal in search, where increased visibility occurs within increasingly competitive and zero-click-friendly result environments.

 

Australian Search Results Saw Massive Impression Gains

In July 2025, SEO professionals across the globe dissected the usual winners and losers from Google's June 2025 Core Update. Behind the familiar industry chatter about algorithm changes and ranking volatility, data from Australian-filtered Search Console reports revealed something extraordinary: websites targeting Australian audiences weren't just seeing modest improvements. They were experiencing explosive growth in search impressions.

The June 2025 Core Update, which rolled out from 30 June to 17 July, was described by Google as "a regular update designed to better surface relevant, satisfying content for searchers from all types of sites." However, industry experts quickly identified it as one of the larger core updates in recent memory, with significant volatility across various sectors.

“The initial rollout seemed to kick in within a few days after the update was announced, specifically on July 2, 2025. Like with all core updates, some sites saw huge declines in ranking visibility, some saw some big improvements and many saw no changes.” (searchengineland.com)

 

The Power of Regional Data Analysis

The difference between global and regional performance during this update demonstrates why country-specific analysis can reveal opportunities that remain hidden in aggregate data. When examining unfiltered Google Search Console data - the default view that aggregates performance across all countries - the impact appeared relatively modest.

 

 
As you can see from these screenshots, the first image (no filtering) shows little change in impressions besides seasonality patterns; whereas the second image (with country filtering) shows a steep increase in impressions, correlating with a steep decrease in CTR, for the same period.

 

Large international websites, for instance, saw their monthly impressions increase from approximately 1.78 million to 1.98 million*, representing steady but unremarkable growth of about 11%*.

However, when the same data was filtered specifically for Australian search results, a completely different narrative emerged. Those same international websites witnessed their Australian impressions skyrocket from around 131,000 to 285,000* - more than doubling their visibility in Australian search results. This represented a staggering 118%* increase that would have remained completely invisible without regional data filtering.

This pattern wasn't an anomaly confined to a single website category. Across different types of sites targeting Australian audiences, the story repeated with remarkable consistency: modest global changes masking explosive regional growth.

The Australian Search Explosion

The scale of impression gains in Australian search results during the June 2025 Core Update was unprecedented. Australian businesses - those with .au country top-level domains - experienced an average impression increase of 224%* during the update period. 85% of sites reviewed in this category saw their impressions more than double.

Car dealership websites exemplify this dramatic shift. Australian automotive brands saw their impressions increase by an average of 163%*, whilst their click volumes remained relatively stable. The result was a fundamental change in the competitive landscape, with brand-focused searches giving way to broader commercial intent queries. Used car listings, financing pages, and lease information suddenly commanded significantly more search real estate.

The story was similar across other sectors. Australian charities witnessed an 88%* average increase in impressions, with content about fundraising, donations, and specific causes gaining substantially more visibility. eCommerce sites targeting Australian consumers saw their impressions grow by 179%*.

 

The Predictable CTR Decline

Alongside the massive impression gains came an expected but significant decline in click-through rates. Australian car dealerships, for example, saw their CTR drop from 7.69% to 2.90%*, a decline of more than 60%.

For SEO professionals, this pattern is neither surprising nor concerning; it's the natural mathematical consequence of dramatic impression increases.

When websites begin appearing for substantially more queries - particularly new queries where they may rank lower initially - the additional impressions often occur at positions less likely to generate clicks. Since click-through rate is simply clicks divided by impressions, a surge in lower-positioned impressions naturally depresses the overall CTR, even when absolute click volumes increase.

However, the modern search landscape adds another layer to this dynamic. Google's increasing use of query fanout and AI-powered features like AI Overviews creates more opportunities for domains to receive impressions, but many of these occur within what's effectively a zero-click environment.

Traditionally, SEOs could expect CTR to gradually recover as average positions improved over time. Now, with more impressions happening in contexts where clicks are less likely to occur - regardless of position - that recovery may be permanently muted.

 

The MUVERA Factor and Local Content Assessment

The Australian data takes on additional significance when viewed through the lens of Google's evolving technical capabilities. Marie Haynes highlighted a crucial development in how Google's systems now evaluate content:

"Prior to Google's invention of the MUVERA technique, the vector search would match the query with documents whose vector indicated they covered a specific topic... Now, the search can determine much more about the specific details within a document. This means that Google got better at finding content that is likely to be helpful." (www.mariehaynes.com)

This technical advancement helps explain why Australian-targeted content saw such dramatic gains. When Google's AI systems assess "the entirety of the content on a page" for helpfulness, websites with comprehensive local information - detailed business addresses, local phone numbers, Australian-specific product information, and content that addresses uniquely Australian contexts - would naturally score higher for Australian searchers.

The Glenn Gabe's analysis adds another crucial piece about the interconnected nature of Google's systems:

"AI Overviews and AI Mode are both within the 'Web Search' bucket and both are 'rooted in Google's core quality and ranking systems.' In other words, they can also be impacted by broad core updates." (www.gsqi.com)

This means the June 2025 Core Update didn't just affect traditional organic results, it also influenced which content appears in AI-powered summaries and features. For businesses targeting Australian audiences, this creates a compound effect where strong local relevance signals could improve visibility across multiple search surfaces simultaneously.

The Australian results suggest that websites maintaining strong local foundations are better positioned to benefit from Google's evolving evaluation methods.

Geographic Signals and Content Ecosystems

The disproportionate impact on Australian search results suggests that geographic relevance signals may have gained significantly more weight in Google's helpfulness evaluation. As the algorithm shifted towards AI-driven content assessment, websites with strong geographic indicators - whether through .au country top-level domains, comprehensive contact information, Google Business Profiles, structured data markup, or properly implemented hreflang tags - may have been rewarded more substantially than in previous updates.

This enhanced focus on geographic relevance aligns with Google's stated goal of surfacing "relevant, satisfying content for searchers." For Australian users searching for local services, products, or information, content that clearly signals its Australian relevance would naturally be considered more helpful than generic international alternatives.

 

A New Search Landscape

The June 2025 Core Update's impact on Australian search results represents part of an ongoing evolution towards AI-driven content evaluation that increasingly prioritises helpfulness. The massive impression gains, coupled with declining click-through rates, suggest Google continues to experiment with delivering more comprehensive, diverse search results, even at the cost of some user engagement efficiency.

If the Australian experience is indicative of Google's broader direction, businesses worldwide should prepare for a search landscape where content quality and genuine helpfulness are increasingly important, where regional variations become more pronounced, and where increased visibility doesn't necessarily translate to proportional increases in traffic.

The Australian data from the June 2025 Core Update serves as both a case study in the importance of regional analysis and a preview of search's AI-driven future. For those paying attention to the signals hidden in their regional data, the transformation is already underway.

September 2025 Update: The Plot Thickens

No sooner had this analysis been published than Google's actions in September 2025 added unexpected complexity to the story. What began as a straightforward examination of Australian impression gains during the June Core Update became entangled in a much larger debate about the reliability of search data itself.

Google Changes How Search Results Work

On 10 September 2025, Google quietly removed a feature that had allowed people to view 100 search results on a single page instead of the usual 10. This change occurred whilst Google's August 2025 Spam Update was still rolling out—a multi-week process designed to target websites violating Google's spam policies.

Within days, businesses checking their Google Search Console reports noticed significant changes in their data. Brodie Clark observed widespread patterns across multiple accounts:

"I'm seeing a noticeable decline in desktop impressions, resulting in a sharp increase in average position. This is across many accounts that I have access to and seems to have started around September 10th when the change first begun." (searchenginejournal.com)

Despite these impression drops, actual website traffic remained stable for most businesses.

The Industry's Focus on Parameter Changes

The SEO community quickly focused on the 100-result parameter removal because it was announced and visible, making it easy to draw correlations with the September data changes. The theory developed that SEO rank tracking tools and AI scraping systems had been artificially inflating impression counts by requesting 100-result pages, registering impressions for websites in positions 1-100 even though real users typically only see the first 10 results.

However, this focus on the September parameter change may have obscured a more significant story that had been unfolding since July.

The Real Timeline: July's Geographic Redistribution

The most crucial discovery came from examining when these dramatic changes actually began. Rather than starting in September with the parameter removal, the analysis revealed that major geographic shifts had been occurring since July, immediately following the June Core Update:

Major market drops began in July: Websites experienced massive decreases of 75-99% in impressions from the USA, Brazil, Italy, Russia, and the United Kingdom starting in July 2025.

Australian gains were simultaneous: The 118-224% impression increases in Australian search results occurred during the same July timeframe.

September revealed, didn't cause: The September parameter changes didn't create these patterns—they exposed them by affecting the masking effect.

What September Actually Changed

The September parameter removal likely did affect some impression reporting, but in a much more limited way than initially theorised. The 40-60% reduction in reported Australian impressions during September could plausibly be attributed to geo-marked tracking tools that were affected by the parameter change. These tools may have been using geographic markers to simulate local traffic, and when the 100-result parameter was disabled, this artificial inflation was reduced.

However, this explains only the September Australian adjustments, not the massive drops that had already been occurring in major markets since July.

The Masking Effect

This discovery reveals that during July 2025, two significant but opposite changes were happening simultaneously:

1. Real improvements in regions like Australia (with genuine 118-224% increases in search visibility)
2. Substantial declines in major markets (with drops of 75-99%)

For businesses looking at their overall international performance, these changes largely cancelled each other out. Australian gains masked the losses in other major markets, creating the appearance of modest, unremarkable change in global reports.

When September's adjustments affected Australian reporting, those underlying losses in major markets became fully visible. This created the appearance of sudden, massive drops for businesses who had been looking only at combined global data—drops that had actually been happening since July but were hidden by the Australian improvements.

The Spam Update: The Likely Primary Driver

While the industry focused on the visible parameter change, the ongoing August 2025 Spam Update - operating quietly in the background - represents a more likely explanation for the broader volatility observed throughout this period. Spam updates historically affect search rankings and visibility as Google's systems reassess which content meets their quality standards.

Since this particular spam update is still technically in progress at the time of writing, the geographic redistribution patterns observed since July may represent genuine algorithmic rebalancing rather than artificial inflation and deflation from tracking tools.

Why the Australian Analysis Remains Valid

The corrected timeline actually strengthens the original June Core Update analysis. The Australian impression gains weren't artificial inflation from tracking tools, they were part of a genuine geographic redistribution that began immediately after the June Core Update in July. The simultaneous drops in major markets and gains in Australia suggest algorithmic changes that favoured geographic relevance and local targeting.

Even after accounting for the September reduction in geo-marked tracking tool effects (the 40-60% Australian drop), substantial underlying improvements remained when compared to pre-Core Update levels, confirming the genuine nature of the algorithmic changes.

(Please note: only 7 days comparison data currently available, more time is needed for a thorough analysis).

The Lesson for Data Analysis

The September 2025 events demonstrate why looking at regional data separately from global averages is crucial. Based on the masking effect observed in this analysis, it's reasonable to theorise that most businesses examining only their overall international Search Console data would have experienced:

• Unremarkable changes during June-August (due to offsetting regional gains and losses)
• Sudden, concerning drops in September (when the masking effect was removed)

Without filtering their data by specific countries, they would theoretically have completely missed both the genuine improvements in some regions and the significant declines in major markets that were reshaping international search visibility.

For any business operating across multiple countries, this suggests that combined global metrics can potentially hide important market-specific changes. The Australian success story was buried within international averages, just as the major market declines were temporarily masked by regional improvements elsewhere.

Have you observed similar regional variations in your search data during this period?

If you've noticed different patterns across specific countries or markets, this could provide valuable context for understanding whether the geographic redistribution observed here is part of a broader global phenomenon.

It's worth noting that Google's August 2025 Spam Update remains ongoing at the time of writing. Since spam updates can continue to affect search results for weeks, the current situation remains fluid and could evolve in any direction. The patterns observed in September may represent temporary fluctuations rather than permanent changes, making it essential to continue monitoring regional performance data as the spam update completes its rollout.

 

Appendix

This analysis is based on a small sample of websites and may not be representative of broader industry trends. Regional filtering of search console data revealed patterns that would have remained invisible in aggregate global reports.

*All data figures represent grouped averages from multiple websites within each category. Percentage growth figures are averages of individual site growth rates, not percentage changes applied to the averaged baseline figures.

Methodology

• Data was collected from Google Search Console for ten websites across different sectors (SaaS, eCommerce, automotive, charities, and professional services).
• Websites were grouped by size (large international 100k+ monthly impressions, large national 100k+, small regional <100k) and market focus (international, national Australia, regional Australia).
• Analysis windows compared pre-update performance (1-30 June 2025) with post-update performance (1-31 August 2025), with year-on-year comparisons (June 2024 vs June 2025) used for seasonality checks.
• Data was analysed both with and without country filtering to demonstrate regional performance variations.
• Individual website performance was averaged within each group to provide representative sector insights while protecting client confidentiality.
• Data analysed indicated a similar trend for New Zealand, however, I did not have enough data for comparison within this article.

Google Search Console screenshots

Key Definitions

• Core Update: A major change to Google's search algorithm that affects how websites are ranked across all search results. These updates typically roll out over several weeks and can significantly impact website visibility.
• Impressions: The number of times a website appears in search results, regardless of whether users scroll down to see it or click on it. Higher impressions indicate greater search visibility.
• Click-Through Rate (CTR): The percentage of impressions that result in clicks to a website. Calculated as clicks divided by impressions (e.g., 100 clicks from 1,000 impressions = 10% CTR).
• Google Search Console: Google's free tool that provides website owners with data about their search performance, including impressions, clicks, and ranking positions.
• Country Filtering: The ability to view search performance data for specific countries or regions, rather than global aggregated data.
• AI Overviews: Google's AI-generated summaries that appear at the top of some search results, providing quick answers without requiring users to click through to websites.
• Zero-Click Searches: Search queries where users find their answer directly on the search results page (through AI Overviews, featured snippets, or other features) without clicking through to any website.