We are excited to announce Domain Exclusion for Microsoft 365 Copilot, a new web search control that gives organizations more choice over which external web sources can be used to ground Copilot responses. As customers bring Microsoft 365 Copilot and Copilot Chat (Copilot) into more business-critical workflows, admins need practical controls that help web-grounded experiences stay aligned with organizational policies, compliance expectations, and trusted source strategies.
Give admins more control over web grounding
Web grounding helps Copilot deliver more timely and relevant answers by allowing Copilot to reference current information from the public web when it can improve the response. With Domain Exclusion, administrators can now specify external sites that Copilot should not use for web grounding, giving organizations a more precise way to align Copilot responses with internal policies, compliance needs, and trusted source strategies.
What is Domain Exclusion?
Domain Exclusion for Microsoft 365 Copilot enables administrators to define domains that are excluded from Copilot web grounding. Once configured, excluded domains are not used in Copilot responses that rely on web grounding. This capability applies to Microsoft 365 Copilot and Copilot Chat web grounding scenarios and is designed to give organizations additional control over which external web sources can influence AI-generated responses.
Organizations can configure up to 1,000 domains for exclusion. The feature is not enabled by default and requires administrator action to configure through the provided PowerShell script. This gives admins flexibility to adopt the control based on their organization’s specific governance requirements.
Figure 1: Info tip for users showing that Admin policy may restrict certain sources with Domain Exclusion for Microsoft 365 Copilot and Copilot Chat.
Why it matters
Customers want the productivity benefits of web-grounded AI while maintaining confidence that Copilot experiences reflect their organization’s policies and risk posture. Domain Exclusion adds targeted control between allowing web grounding broadly and turning web search off entirely. Admins can continue to enable web-grounded answers where they add value, while excluding domains that are not appropriate for their environment.
This is especially important for organizations with strict compliance obligations, brand safety requirements, regional content considerations, or internal policies around approved sources. By helping admins reduce the influence of unwanted or non-compliant web sources, Domain Exclusion supports a more governed approach to AI adoption.
How admins can get started
Admins can configure Domain Exclusion using the Configure Tenant Domain Exclusions PowerShell script. The script supports common configuration tasks, including creating a new exclusion list from a CSV file, updating an existing configuration, exporting the current configuration, deleting a configuration, and generating a template CSV file. Learn more at aka.ms/copilot/DomainExclusion.
- Review the domains your organization wants to exclude from Copilot web grounding.
- Prepare a CSV file with the required domain information.
- Run the PowerShell script as a Search Administrator or Global Administrator.
- Validate the configuration and update it as organizational policies evolve.
Closing
Domain Exclusion gives organizations another practical control to adopt Microsoft 365 Copilot with confidence—helping admins shape how web-grounded experiences align with their policies, compliance requirements, and trusted source strategies. As AI becomes more deeply embedded in everyday work, capabilities like Domain Exclusion help organizations move faster without giving up the transparency, security, and governance they need. Domain Exclusion builds on Microsoft 365 Copilot web search controls, giving admins a more targeted way to manage which external domains can be used to ground Copilot responses.
Related
- Domain Exclusion Learn documentation - https://aka.ms/copilot/DomainExclusion
- Domain Exclusion PowerShell script - https://aka.ms/Copilot/DomainExclusionScript
- Data, privacy, and security for web search in Microsoft 365 Copilot and Microsoft 365 Copilot Chat | Microsoft Learn
- How web search works in Microsoft 365 Copilot Chat and agents | Microsoft Support
