Why Your Google Search Console Impressions Dropped in Mid‑September

Starting around September 10–15, 2025, many SEOs and webmasters began noticing a significant decline in Google Search Console (GSC) impressions. For many, this appeared sudden and severe, despite no real drop in rankings or organic traffic. The answer lies in a recent Google change that removed support for the &num=100 parameter, dramatically affecting how impressions are counted. This blog breaks down what happened, what changed in Google’s systems, and how you can adjust your measurement strategy moving forward.

Widespread Reports of Sudden Impression Drops

Starting in mid-September, discussions exploded on platforms like Reddit and SEO forums. Hundreds of users across industries reported a “cliff-drop” in impressions in their Google Search Console data. Many saw impressions fall by 20–50% or more within just a few days, even though content had not changed, and keyword targeting remained consistent.

Interestingly, the decline didn’t correlate with drops in clicks or revenue. In fact, some users reported better click-through rates (CTR) and improved average ranking positions, despite the lower impression volume. This signaled a reporting issue rather than an algorithmic penalty or ranking drop.

For newer websites or pages ranking beyond the first page of results, the decline in impressions was even more dramatic. Reports showed that pages previously generating thousands of impressions per day were now showing only hundreds. That level of change raised alarms, prompting speculation and eventually confirmation of a behind-the-scenes technical shift by Google.

The Core Cause: Google Disables the &num=100 Parameter

Historically, Google allowed users and bots to add the &num=100 parameter to search URLs, which forced the search engine to display 100 results per page. This was widely used by SEO tools and scrapers to gather broad SERP data efficiently, particularly for tracking long-tail keywords and pages that ranked beyond position 10.

In September 2025, Google quietly disabled this parameter. As a result, all search requests defaulted back to the standard 10 results per page. This meant bots and SEO tools could no longer easily load or record visibility beyond the first page of results, fundamentally changing how impressions were counted.

Previously, even if your page ranked on page 3 or 6 of Google, it could still generate impressions if scraped by a rank-tracking tool or bot using &num=100. Now that functionality is gone, those deeper-ranked impressions aren’t being recorded as they once were. The effect is a massive drop in reported impressions, especially for keywords that don’t rank in the top 10.

Why the Change Impacts GSC but Not Your Traffic

This shift created a discrepancy between actual site traffic and what GSC reports. Many sites continue receiving similar volumes of organic visits, but impressions reported in Search Console are down significantly. That’s because GSC impressions only count when a URL visibly appears in search results—something now far less likely for lower-ranked content.

With bots no longer pulling full 100-result pages, many impressions that were once artificially inflated by machine activity have vanished. In that sense, the data now better reflects real user visibility, not automated scraping. The trade-off is a steeper impression drop, especially for sites that depended heavily on long-tail or lower-ranking keywords.

Clicks and CTR data, meanwhile, remain relatively stable. Because the denominator (impressions) has shrunk and the numerator (clicks) has not changed as much, CTRs are now mathematically higher. This might seem like improved performance at first glance but is largely a result of cleaner impression counts, not more effective SEO.

How to Know if It's a Reporting Drop or a Real SEO Issue

Not every drop in impressions is harmless. It’s important to assess whether your visibility issue is purely due to the measurement change or if you were also impacted by other ranking factors. Start by checking if your actual organic traffic from Google has declined in tools like Google Analytics or server logs.

If clicks are stable or CTR is improving, and your traffic hasn't fallen significantly, you’re likely seeing a reporting-only issue. Also check your average ranking position. Many SEOs report that average position improved post-update—because lower-position impressions are no longer dragging down the average.

However, if both clicks and traffic are down along with impressions, you may be dealing with a real visibility problem. Investigate deeper by auditing your content, checking for indexing issues, and reviewing Google's latest algorithm updates to see if your site may have been hit for quality, spam, or relevance concerns.

Other Updates That May Be Complicating the Picture

While the &num=100 parameter change is the main cause of recent GSC impression drops, it coincided with other updates that may affect your site. Most notably, Google rolled out a spam update starting in late August 2025, with completion around September 22.

This spam update targets low-value, deceptive, or AI-generated content that fails to provide helpful or original information. If your impression drop started before September 10, it’s more likely tied to the technical change. If it continued through the rest of September, you may have also been affected by this content-quality update.

Google’s increasing focus on AI-generated content, infinite scroll search results, and new SERP layouts is also creating noise in impression tracking. As Google shifts toward AI answers and summaries, traditional link-based impressions could drop, even if user satisfaction or engagement improves.

Common Patterns Emerging Across Affected Websites

Across Reddit threads and SEO case studies, the same patterns are surfacing. First, the average position often improves even as impressions fall. Second, the drop is more severe on desktop than mobile for some sites, likely due to how desktop SERPs are paginated.

Third, sites that rely on long-tail content or rank for many queries beyond position 10 saw the steepest impression declines. Fourth, clicks remained steady or fell only slightly, reinforcing that traffic wasn’t lost—just the way impressions were measured.

Finally, some SEOs have questioned whether prior GSC impression data was ever truly accurate. If bots and scraping tools were responsible for inflating counts beyond what real users ever saw, this change may be more of a long-overdue correction than a flaw.

What You Should Do Now to Adapt

The most important step is to recalibrate your expectations. Impression data from September 2025 onward cannot be compared to previous months without acknowledging this change. Adjust your internal reporting baselines and update stakeholders accordingly to prevent confusion over performance.

Next, focus more on user-centric KPIs. Metrics like organic sessions, bounce rate, engagement time, and conversions will tell you more about true performance than impressions alone. Pay close attention to what’s happening at the keyword and content level through both GSC and your analytics tools.

You should also audit your content strategy. If a lot of your traffic came from keywords ranking beyond the top 10, this change should prompt a renewed focus on content that can break into higher visibility zones. Prioritize quality, relevance, and authority—especially in light of the recent spam update.

Finally, keep monitoring your tools. Rank tracking platforms are adjusting their methods to account for the new limits, and further changes from Google are likely. Stay engaged with SEO communities and Google Search Central announcements to remain agile.

Final Thoughts: New Metrics, New Mindset

The dramatic drop in Google Search Console impressions starting mid-September 2025 has been alarming to many, but it's largely the result of a shift in how Google processes and counts visibility data—particularly the removal of the &num=100 parameter that once inflated lower-ranking impressions. For most websites, this is not a sign of declining performance, but rather a change in reporting accuracy.

Still, this shift is a wake-up call for marketers and SEOs to revisit their metrics. Impressions are now a less reliable indicator of visibility than before. It's time to focus on real engagement: clicks, conversions, and content that ranks on page one. With Google's continued evolution toward AI-generated summaries and zero-click results, technical SEO must align more tightly with real user experience.

At SmithDigital, we help businesses interpret and adapt to the ever-changing SEO landscape. Whether you're tracking performance, adjusting content strategies, or navigating the fallout of Google’s latest update, our team can help you make sense of the data and stay ahead of the curve.

Need help adjusting your SEO strategy or understanding your new GSC data?
Contact SmithDigital today to schedule a consultation with our technical SEO experts and get actionable insights tailored to your site.