The platforms at a glance
| Platform | Status | How you buy | Can you choose the topics? |
|---|---|---|---|
| ChatGPT | Self-serve since May 2026 in the US; UK from June; 60+ countries by late September | OpenAI Ads Manager | Yes, with context hints |
| Google AI Overviews | US since October 2024; 11 more English-language markets from December 2025 | Existing Search, Shopping and Performance Max campaigns | No separate targeting or reporting |
| Google AI Mode | Testing in the US | Not generally available | – |
| Microsoft Copilot | Running in English, French and German markets | Microsoft Advertising | Standard Microsoft targeting |
| Perplexity | Launched 2024, being wound down by the end of 2026 | Closed to new programmes | – |
What it means for B2B
- ChatGPT is the only one where you pick the buyer questions. That makes it the natural place to start a B2B test.
- Google AI Overview ads come with your search budget. You can't target or report on them separately, so treat them as part of search.
- Copilot rides on Microsoft Advertising. If you already run Microsoft Ads, you may already appear there.
- Perplexity is a visibility play, not an ad play. Being cited in its answers still matters.
Note on the UK
The December 2025 AI Overview ad expansion covered Australia, Canada, India, Indonesia, Kenya, Malaysia, New Zealand, Nigeria, Pakistan, the Philippines and Singapore. The UK wasn't on that list.
This page changes as platforms change. We review it every month.
How to choose where to test
| If you... | Start with |
|---|---|
| Want to choose the buyer questions | ChatGPT ads |
| Already spend heavily on Google search | Check your AI Overview exposure in existing campaigns |
| Sell to corporate Windows users | Microsoft Advertising, including Copilot |
| Care about researchers and analysts | Perplexity visibility, not ads |
What we check every month
- New markets for ChatGPT ads and AI Overview ads.
- Changes in OpenAI's ad policy and targeting.
- Whether Google AI Mode ads leave testing.
- Microsoft's Copilot ad formats.
Questions
What about other AI assistants?
We review new AI ad products every month and add them to this page when B2B advertisers can buy them.
Is ChatGPT available to advertisers outside the US and UK?
Yes. By late September 2026 ads were live in more than 60 countries, including European markets from August.
Which platform has the most B2B buyers?
Nobody publishes a reliable split. Track your own buyers' questions in each engine and see where competitors are named.
Start here: AI ads for B2B. More articles in AI advertising strategy.