Falling paid search impressions are the wrong number to panic about

By Olly, AEOscore founderPublished 18 August 20265 min read

Reviewed quarterly; figures re-verified before each update.

Falling paid search impressions are the wrong number to panic about. Impressions are a count of how often Google chose to render your ad on a page it now fills with its own answer first, and that count can fall a long way while the number of people who want to buy from you does not move at all. Before you cut a pound of budget, check the two figures that cannot be reallocated, compressed or misattributed: total revenue (or total orders) and total qualified enquiries, this year against last. If those held, you have a routing change, not a demand change. Cutting budget on a routing change is how a measurement problem becomes a real one.

The tidy story

A UK B2B ecommerce marketer opens Google Ads, sees Search impressions down, say, by a fifth year on year, opens GA4, sees a new line called chatgpt.com in the referral report, and joins the dots: AI is eating paid search, so paid search should be cut. It is a tidy story. It is also usually only one part in three true, and the part that is true does not point to the conclusion.

There are three things going on. Broad match, Performance Max and AI Max move impressions between campaign types, so a Search campaign can shrink while the account holds; that is bookkeeping. AI Overviews and AI Mode take the first screen and push ads down it, so fewer ads are seen and counted per search; that is Google’s layout, and Seer Interactive measured paid click-through on AI Overview queries falling from 19.70% to 6.34% between June 2024 and September 2025 across 42 organisations’ informational terms. And yes, some buyers now research in ChatGPT, Gemini and Perplexity, where Ofcom counted 1.8 billion UK visits to ChatGPT in the first eight months of 2025 alone. Only the third one is your buyers moving, and even that one is not a reason to cut.

Why impressions mislead

An impression is a rendering event, not a person. When Google shows an AI Overview and, say, one ad instead of four, three impressions vanish and zero buyers do. When Performance Max wins a query your exact match campaign used to win, one impression moves and zero buyers do. When Google stopped honouring the num=100 parameter in September 2025, Search Console impressions fell off a cliff overnight and zero buyers did, and that one was not even in Google Ads. The number wobbles for reasons that have nothing to do with demand, which is why it makes a poor alarm.

The check that settles it: total revenue (or total orders) and total qualified enquiries, thirteen months, from your order system or CRM, not from a channel report. If they held while paid impressions fell, the buyers found another door.

Where the buyers went, and why the referral line understates it

The chatgpt.com line in GA4 is real and it is a floor. In-app browsers and some assistant clients pass no referrer, so the visit lands as Direct. Plenty of people read your name in an answer and search for you by name a day later, which lands as branded organic. Some never click at all: they get the price band and the lead time from the answer and pick up the phone. So read three lines together, AI referrals, Direct to deep pages, and branded search impressions in Search Console. When all three rise while paid impressions fall, the routing story is confirmed even though no single line proves it.

And the visits that do arrive are worth having. Adobe Analytics reported AI-referred visitors converting 31% more than other traffic over the 2025 holiday season; Semrush research in June 2025 valued an AI-search visitor at 4.4 times an organic one. Retail-weighted, vendor-published, treat the size as directional. The direction is the same across the recent datasets, and it was not always: Adobe’s own numbers only flipped positive during 2025. It makes sense once the research has happened before the click.

What I would change

Cut the research keywords, keep the buying ones. The “what is” and “how do I” terms are the ones assistants now answer for free, and they were always your worst converters. Bottom-funnel, part-number and competitor terms are where a buyer who has finished researching goes. Hold or raise those.
Unblock the AI crawlers. Ten minutes in robots.txt and your CDN settings. If GPTBot, OAI-SearchBot, PerplexityBot and ClaudeBot cannot read your pages, the assistants answer your buyers’ questions from somebody else’s site, and no amount of good writing helps.
Make the top ten buyer-question pages quotable. Price bands, lead times, minimum orders, compatibility, delivery. First sentence under each heading answers the question outright.
Measure the thing that is actually moving. Which engines mention you, and which mention your rivals instead, on the questions your buyers ask. Nothing in Google Ads or GA4 can show you that; it is the number I built AEOscore to show.

The most expensive mistakeis still the one from the top of this piece: cutting paid budget on what is only a routing change, in the month your rivals’ ads get cheaper.

The long version

I have written the full diagnosis up as a guide: the three causes with every figure dated and sourced, a six-step triage you can run in an afternoon, a decision table that maps your pattern to a first action, and a 30-day plan split into paid, site and measurement. Why paid search impressions are falling while ChatGPT referrals rise: a diagnostic guide for UK B2B ecommerce. Run the six checks before the budget meeting. Figures in this post checked 18 August 2026; each one is dated to its source in the guide.