Microsoft Security Copilot is an AI assistant for cybersecurity professionals that uses generative AI and Microsoft's global threat intelligence — signals from 84 trillion data points processed daily — to help analysts detect, investigate, and respond to security incidents faster. It became generally available in April 2024. In March 2025, Microsoft extended it with autonomous AI agents that can handle routine security tasks on their own.

Announced in March 2023, Security Copilot reached general availability on April 1, 2024 with pay-as-you-go pricing of $4 per hour per Security Compute Unit. It integrates with Microsoft's full security product portfolio including Defender XDR, Sentinel, and Microsoft Entra. The AI processes natural language questions and returns findings that would otherwise require hours of manual investigation — for example, tracing how an attacker moved through a network. In March 2025, Microsoft unveiled six autonomous AI security agents capable of independently triaging phishing alerts, flagging identity risks, and optimizing access policies. Microsoft's internal studies found that security analysts were 22% faster and 7% more accurate with Security Copilot than without it. As of November 2025, it is included at no additional cost for Microsoft 365 E5 customers.