ChatGPT Ads Agencies: Every Agency Selling ChatGPT Ads, Ranked

Our analysts compiled every agency we could document selling or running ChatGPT ads, 29 agencies and agency groups in all, drawing on OpenAI's own announcements, agency press releases and case studies, trade press from nine countries, and agency service pages published between February 9 and October 28, 2026, to show what the ChatGPT ads agency market looks like as of Q4 2026.

ChatGPT ads began as a closed test in the US on February 9, 2026, sold through a handful of large agency groups. On May 5, OpenAI opened its self-serve Ads Manager and listed dentsu, Omnicom, Publicis, and WPP as agency partners, alongside technology partners such as Criteo, StackAdapt, and Pacvue. By October 21, ads were running in 89 countries for more than 100,000 advertisers. That growth has pulled far more agencies into the business than the original four, and advertisers now choose among global holding companies, regional agency groups, and small specialists that all offer ChatGPT ads management. This report sorts them by how much public evidence stands behind each one.

Our analysts searched OpenAI's announcements, agency newsrooms and LinkedIn posts, trade press in nine languages, and agency service pages for every agency that sells or runs ChatGPT ads. Each agency earned points for four kinds of evidence: whether OpenAI listed it as a partner or the agency or trade press reported a partner or pilot role, how many client brands are publicly tied to its ChatGPT ads work, how many markets that work covers, and whether a live campaign has been described in public. Ad prices and campaign results are left out of this report. For the brands buying the ads, see our tracker of every confirmed advertiser on ChatGPT.

In the following sections, we compare the full ranking, the holding companies OpenAI lists as partners, the client campaigns agencies have disclosed, where each agency has documented work, and when each one entered the market.

The Full Ranking of ChatGPT Ads Agencies

We start with the complete ranking because it answers the first question most advertisers have: which agencies can show real ChatGPT ads work, and how much proof stands behind each claim. Each agency's score adds partner status, disclosed client brands, documented markets, and a described live campaign, for a maximum of 100 points.

Source: Top GEO Agencies analysis of public ChatGPT ads evidence for 29 agencies and agency groups, conducted October 2026.

Source: Top GEO Agencies analysis of public ChatGPT ads evidence for 29 agencies and agency groups, conducted October 2026.

Key Findings

• The five agencies OpenAI lists as partners hold the top five places, and Cosmo5 ties Havas at 70 points on the strength of seven disclosed clients in France and Spain.
• Below the top six, scores drop to 46 or less, because no other agency combines a confirmed partner role with disclosed clients across several markets.
• For advertisers, the ranking separates agencies whose ChatGPT ads work can be checked against client brands and OpenAI's own announcements from agencies whose evidence is a service page or an anonymized case study.

The Holding Companies OpenAI Lists as Partners

OpenAI built its ad business through the big media holding companies first, so we looked at which ones it has listed, in which launches, and through which agency units. This matters to advertisers because these are the agencies OpenAI itself points to as it opens each new market.

Source: OpenAI; iWorld; Storyboard18; Top GEO Agencies analysis, conducted October 2026.

Source: Top GEO Agencies analysis of public ChatGPT ads evidence for 29 agencies and agency groups, conducted October 2026.

Key Findings

• WPP Media and Omnicom Media appear in the most OpenAI launches, four each, and they were OpenAI's first two agency partners in India.
• France had the widest partner group of any launch: Stratégies and Journal du Net report that the five holding companies plus Serviceplan's Mediaplus and Cosmo5 handled the August 24 launch, which ran only through partner agencies and technology platforms for its first week.
• For a multinational advertiser, any of the five covers the largest markets, and the difference between them lies in which local units have client work on the record in the countries that matter to that advertiser.

Which Client Campaigns Agencies Have Disclosed

Partner status shows an agency can buy ChatGPT ads, and a client brand on the record shows it already has. We collected every brand that a source ties to a specific agency's ChatGPT ads work, along with the market where that work ran.

Source: Agency releases, case studies, and trade press listed in Sources; Top GEO Agencies analysis, conducted October 2026.

Source: Top GEO Agencies analysis of public ChatGPT ads evidence for 29 agencies and agency groups, conducted October 2026.

Key Findings

• The US has the most disclosed client brands at seven, followed by France, Germany, and the United Kingdom with five each.
• Omnicom Media has the widest gap between activity and disclosure: it told ADWEEK that more than 30 of its clients secured placements in the February pilot, yet Nissan in the Netherlands is the only brand a public source ties to its ChatGPT ads work.
• Advertisers vetting an agency can ask for the client brands behind its ChatGPT ads claims, since 20 of the 29 agencies have not put one on the public record.

Where Each Agency Has Documented ChatGPT Ads Work

OpenAI has opened ChatGPT ads one market at a time, and agency footprints follow those openings. We mapped each agency to the countries where a source places its ChatGPT ads work, which shows advertisers outside the US which agencies have local experience. OpenAI's Southeast Asia and Taiwan launch counts as one market group.

Source: Top GEO Agencies analysis of public ChatGPT ads evidence for 29 agencies and agency groups, conducted October 2026.

Source: Top GEO Agencies analysis of public ChatGPT ads evidence for 29 agencies and agency groups, conducted October 2026.

Key Findings

• The US leads with 12 agencies, and France is second with 8, where the August 24 launch ran only through partner agencies and technology platforms for its first week.
• Asia has few documented agencies, all of them local firms or holding-company units: dentsu, Hakuhodo DY ONE, and CyberAgent in Japan, Nasmedia in South Korea, and WPP Media, Omnicom Media, and AGL-Hakuhodo in India.
• Outside the US and France, the choice of agencies narrows quickly: in 14 of the 18 markets we tracked, four or fewer agencies have documented ChatGPT ads work.

When Agencies Entered the ChatGPT Ads Market

The order in which agencies arrived shows advertisers how long each one has worked on the platform, which counts for a lot in a channel this new. We dated each agency by its earliest documented ChatGPT ads activity and set those dates against OpenAI's main launches.

Source: OpenAI; agency releases and trade press listed in Sources; Top GEO Agencies analysis, conducted October 2026.

Source: Top GEO Agencies analysis of public ChatGPT ads evidence for 29 agencies and agency groups, conducted October 2026.

Key Findings

• Nine of the 22 dated agencies first appeared from August on, as OpenAI opened Brazil, Mexico, Europe, India, and Southeast Asia.
• DEPT is the only agency outside the big holding companies with documented work from the closed US test, which began almost three months before self-serve buying opened.
• Advertisers weighing experience can treat the four agencies active before May 5 as the longest-tenured, while every other agency has run ChatGPT ads for six months or less.

What the Evidence Shows About the ChatGPT Ads Agency Market

The ChatGPT ads agency market has split into three layers in less than nine months. The holding companies OpenAI lists in its announcements hold most of the disclosed client relationships and the widest market coverage. A second layer of regional groups, from Cosmo5 in France and Spain to CyberAgent in Japan and Nasmedia in South Korea, holds launch-partner or pilot roles in single markets. Below them, 16 independent agencies sell ChatGPT ads management, and 14 of them have yet to put a client brand on the record.

OpenAI has not published an agency partner directory, so outside its own launch announcements, partner claims rest on agencies' own statements. Technology platforms give agencies a second route to the same inventory: Gamned! buys ChatGPT ads through StackAdapt, and Kepler runs its clients' campaigns through Pacvue.

OpenAI's latest expansion, on October 21, added 26 countries, 14 of them in Latin America, and brought ChatGPT ads to 89 countries in total. As of October 28, none of the 29 agencies in this report has documented ChatGPT ads work in any of those 26 countries.