Why your Search Console impressions dropped (and how to tell if it matters)

The 7 causes, and the fingerprint of each

The 2026 impressions bug

On April 3, 2026, Google posted on its Data anomalies in Search Console page that a logging error had kept Search Console from reporting impressions accurately since May 13, 2025. The page now dates the problem from May 13, 2025 until April 27, 2026, and marks it resolved. Google's note says only impressions and the metrics built on them (CTR and average position) were affected. Clicks were not.

What that means for you:

• Impressions in your reports for May 2025 to April 2026 are higher than what really happened. Google did not go back and correct the old data (Search Engine Land, April 2026).
• When the fix rolled out in April 2026, many sites saw impressions step down while clicks stayed level.
• CTR for that period looks lower than it really was, because the same clicks sit on inflated impressions.

The September 2025 num=100 change

Around September 10 to 14, 2025, Google stopped returning 100 results per page when a URL asked for it with &num=100. Rank trackers and scrapers had used that parameter for years to read positions 1 to 100 in one request. A Google spokesperson said the parameter "is not something that we formally support" (Search Engine Land, September 2025).

Those bot requests had been logging impressions for pages at deep positions, often 20 to 100, that no person ever scrolled to. When they stopped, the impressions went with them. In an analysis of 319 Search Console properties, Tyler Gargula of LOCOMOTIVE found 87.7% of sites lost impressions and 77.6% lost unique ranking queries (Search Engine Land, September 2025).

What it looks like in your data: impressions fall in a step in mid-September 2025, mostly on desktop. Clicks barely move. Average position improves, because the deep positions dropped out of the average. Nothing about your real visibility changed.

Which comparisons you can trust in late 2026

Because of these two changes, impressions, CTR and average position from before late April 2026 are not comparable with data after it. Clicks are fine across the whole period.

Year-over-year impressions comparisons become clean again from May 2027, when both windows fall after the fix. For a client report, say it in one line: "Search Console over-counted impressions from May 2025 to April 2026, so we compare clicks across those months."

A 15-minute check

1. Open Performance > Search results, set the date to the last 16 months and turn on all four metrics.
2. Look for steps down in mid-September 2025 or in April 2026 with flat clicks. If that is all you see, your traffic did not drop. It is a reporting change.
3. If the drop is recent, use Date > Compare: last 28 days vs the 28 days before.
4. Open the Queries tab and sort by Impressions difference. Did your main queries lose positions? That is a ranking loss. Check the dates against Google's Search Status Dashboard and our Google core update 2026 page.
5. Open the Pages tab. If a few URLs lost almost all impressions, check them with URL Inspection and look at Indexing > Pages for new "not indexed" reasons.
6. Look at the same months last year in clicks. A dip in both years is demand, not you.
7. If only the last 1 to 3 days look low, wait. Search Console data is usually ready in 2 to 3 days; see Search Console data delay.

Also check that you are looking at the right property. If the site moved from http to https or to a new domain, a URL-prefix property for the old address will show a cliff. A Domain property covers every protocol and subdomain.

What AI Overviews do to impressions

AI Overviews usually do not cause an impressions drop. When your page is linked in an AI Overview, Google counts an impression, and the whole Overview takes one position (Search Console Help). The AI pattern is the opposite chart: impressions flat or up, clicks down. If that is what you see, read impressions up, clicks down.

A fictional example

brightsmile-dental.com (fictional) saw impressions fall 38% from March to May 2026, while clicks went from 1,880 to 1,850 a month. The step was in April 2026, matching Google's impressions bug fix. Its "last 12 months" report made the drop look like a disaster. The clinic switched its monthly report to clicks and bookings, and now compares impressions only between months after April 27, 2026.