ChatGPT advertising is no longer an experiment. Adthena’s September 2026 data pulse puts a number on the shift: the weekly count of unique ChatGPT advertisers rose from 7,306 in the week of July 9 to 12,075 by August 31, a 65% climb across eight weeks. The count peaked at 13,009 in the week of August 10 before a mid-period dip and recovery.
The report lands as OpenAI’s ad product expands aggressively. Sponsored placements reached 31 European markets on August 24 and later added India and seven Asian markets, pushing the public footprint past 60 countries. OpenAI has also said the ads business reached a $1 billion annualized revenue run rate in under 200 days. That pace helps explain why brands are rushing in.
One caveat: Adthena tracks unique advertiser participation through live ChatGPT sessions, not spend or impression volume. First-party metrics exist in ChatGPT’s Ads Manager, but they don’t show competitive share. Third-party visibility gaps remain.
Short-tail queries take over AI Overview ads
The more surprising finding is in Google’s AI Overviews. Adthena reports that one-to-two-word queries now command more than half of AI Overview ad appearances in every market measured. In the US, short queries made up 62.9% of 288.6 million appearances; the EU saw 62.4%, Australia 56.5%, and Asia 74.4%.
That reverses the firm’s own earlier research. In April and June, three-to-four-word queries captured the majority. The September report does not explain the mechanism—it could reflect a change in how Google selects eligible queries, shifts in query composition, or measurement differences. Marketers should treat the shift as a signal, not a settled rule.
Why this matters for search budgets
If you’re still assuming AI search is a long-tail game, your keyword coverage may be pointing the wrong way. The data suggests brands optimized for short, high-intent queries are now better positioned in AI Overviews.
- Audit one-to-two-word query visibility in Google Ads Search Terms reports
- Track ChatGPT advertiser counts and regional availability weekly
- Benchmark your AI search visibility in every market you target
A market still finding its shape
Adthena’s regional leaderboard shows how localized the opportunity remains. Booking.com is the only brand appearing in the top five across the US, EU and Asia. Otherwise, local players hold their home turf: Carvana leads US AI Overview appearances at 1.2%, Dan Murphy’s leads Australia at 4.3%, and Hostinger tops Asia at 3.6%.
In electronics, Temu leads US click share at 28.3%, while Argos holds the UK at 17.97%. Apparel is even more fragmented—no global winner emerges. The takeaway: AI search ads reward category visibility and local relevance right now, not a one-size-fits-all playbook.
What to do next
Start with short-tail coverage. The ChatGPT side is still early, but advertiser participation is a leading indicator of rising competition. If you buy search ads, the window to test before auctions get crowded is closing.
Source: PPC Land
