There isn’t any public, reliable source that says which Azure region gets “most ChatGPT traffic,” so the honest answer is: that specific traffic split is not publicly disclosed. What is public is that OpenAI/ChatGPT has used Microsoft Azure infrastructure broadly, and Microsoft has discussed Azure regions and traffic rerouting in the context of outages, but not a ranked region-by-region traffic share for ChatGPT.

What can be said safely

  • ChatGPT runs on Microsoft Azure-backed infrastructure, but OpenAI does not publish a “most-used Azure region” breakdown.
  • Azure outages and routing changes have affected services globally, which suggests traffic can be distributed and shifted across healthy infrastructure rather than tied to one fixed region.
  • Some OpenAI services have also been made available through Azure OpenAI in specific government and enterprise environments, but that is separate from consumer ChatGPT traffic.

Practical interpretation

If someone claims a single Azure region handles most ChatGPT traffic, that is usually speculation unless it comes from an internal leak or a direct Microsoft/OpenAI disclosure. Based on public info, the safer conclusion is that traffic is likely load-balanced across multiple regions and can move during incidents.

TL;DR

No public source confirms one Azure region as the main destination for most ChatGPT traffic, and Microsoft/OpenAI have not published that detail.