Department of War Launches OpenAI’s ChatGPT Mil on GenAI.mil

The Department of War launched OpenAI’s ChatGPT Mil on its GenAI.mil platform on August 31, 2026, adding a custom version of the chatbot accredited for Controlled Unclassified Information at Impact Level 5 and built to support more than 3 million Department personnel.

The Department said the launch marks the adoption phase of an enterprise partnership established with OpenAI in 2025. ChatGPT Mil’s core experience centers on chat, files, projects, and custom GPTs, with additional features sequenced over time. The system supports document-heavy unclassified work across the Department, including planning, policy, logistics, and administration. According to the Department, the deployment accelerates routine tasks and frees up time for more critical projects across the Joint Force, and integrating ChatGPT Mil alongside existing frontier AI capabilities establishes a multi-model ecosystem on the platform.

From Partnership Announcement to Deployment

The launch follows an integration effort the Department and OpenAI announced earlier in the platform’s life. In the release announcing that partnership, the Department said GenAI.mil had surpassed one million unique users within two months of deployment, with adoption spanning every military service, and reported 100% uptime since launch. That release framed the OpenAI integration as a direct execution of the Department’s AI Acceleration Strategy and the White House’s AI Action Plan.

OpenAI, in a February 9, 2026, announcement, said it would deploy a custom version of ChatGPT on GenAI.mil approved for the Department’s unclassified work, running in authorized government cloud infrastructure with built-in safety controls and protections for the Department’s data. The company said data processed on GenAI.mil remains isolated to the government environment and is not used to train or improve OpenAI’s public or commercial models. OpenAI described the system’s intended tasks as summarizing and analyzing policy and guidance documents, drafting and reviewing procurement and contracting materials, generating internal reports and compliance checklists, and supporting research, planning, mission support, and administrative workflows. The company also said the models deployed on the platform incorporate safeguards at the model and platform level and support all lawful uses.

Safeguards in OpenAI’s Agreement With the Department

OpenAI has separately detailed the guardrails attached to its broader work with the Department. In a February 28, 2026, post describing its agreement for deploying advanced AI systems in classified environments, the company listed three red lines: no use of its technology for mass domestic surveillance, no use of its technology to direct autonomous weapons systems, and no use of its technology for high-stakes automated decisions. OpenAI said the deployment is cloud-only, that it retains full discretion over its safety stack, and that cleared OpenAI personnel remain in the loop.

In a March 2, 2026, update to that post, OpenAI said it worked with the Department to add contract language making explicit that its tools will not be used to conduct domestic surveillance of U.S. persons, including through the procurement or use of commercially acquired personal or identifiable information. The company said the Department also affirmed that OpenAI’s services will not be used by Department of War intelligence agencies such as the NSA, and that any services to those agencies would require a new agreement. The Department plans to convene a working group of leaders from frontier AI labs, cloud providers, and its policy and operational communities, in which OpenAI said it will participate.

The GenAI.mil Platform’s Expansion

GenAI.mil itself launched on December 9, 2025, with Google Cloud’s Gemini for Government as the first of several frontier AI capabilities the Department said would be housed on the platform. The Department credited the AI Rapid Capabilities Cell within its Office of Research and Engineering with the launch and said all tools on the platform are certified for Controlled Unclassified Information at Impact Level 5. “We are pushing all of our chips in on artificial intelligence as a fighting force,” Secretary of War Pete Hegseth said in that release.

On December 22, 2025, the Department entered into an agreement with xAI to deploy capabilities based on the Grok family of models on GenAI.mil, targeting initial deployment in early 2026 at Impact Level 5, with users also gaining access to real-time global insights from the X platform. On January 12, 2026, the Department launched an AI Acceleration Strategy organized around warfighting, intelligence, and enterprise operations, naming GenAI.mil among seven Pace-Setting Projects and describing its enterprise role as providing Department-wide access to frontier generative AI models for all personnel at Impact Level 5 and above classification levels.

The Department has also extended AI deployments beyond unclassified environments. In a separate release, it said it had entered into agreements with eight frontier AI companies — SpaceX, OpenAI, Google, NVIDIA, Reflection, Microsoft, Amazon Web Services, and Oracle — to deploy their capabilities on the Department’s classified networks at Impact Levels 6 and 7 for lawful operational use. That release said more than 1.3 million Department personnel had used GenAI.mil within five months, generating tens of millions of prompts and deploying hundreds of thousands of agents.

The Department said the ChatGPT Mil launch supports the White House’s AI Action Plan, which the White House released on July 23, 2025, identifying more than 90 federal policy actions across three pillars: accelerating innovation, building American AI infrastructure, and leading in international diplomacy and security. Through the Chief Digital and AI Office and the Office of the Under Secretary of War for Research and Engineering, the Department said it will continue scaling frontier AI across the Joint Force, with additional ChatGPT Mil features sequenced over time.