Copilot Domain Exclusion: What Changed and What Admins Should Check

There is a big difference between turning off Copilot web grounding and saying “web grounding is useful, but I do not want results from these domains.” Domain Exclusion is designed for the second scenario.

Microsoft introduced Domain Exclusion as a more targeted web grounding control and included it in the July Copilot updates. The idea is straightforward: administrators can maintain a list of domains that should not be used to ground Copilot web responses.

The rollout itself has not been quite as straightforward, so availability is the first thing to verify.

What the control is for

Domain Exclusion is useful when your organization has a known set of external sources it does not want influencing web-grounded answers. That might include an untrusted content network, a domain that conflicts with an internal sourcing policy, or a site that repeatedly creates misleading context for a specific business process.

This is more precise than disabling web search for everyone.

It is not a replacement for blocking users from visiting a website, and it is not a universal content-verification system. The control affects the sources used for Copilot web grounding.

Do not build your rollout on an old screenshot

Microsoft's Domain Exclusion announcement was updated on 4 August and pointed readers to a later status announcement. That is exactly why I would verify current availability in Microsoft documentation and your Message Center before writing an internal implementation guide.

If the setting is unavailable, do not tell support to keep refreshing the portal. Record the rollout state and wait for the supported control to be available again.

Build a test with two recognizable domains

When the feature is available in your tenant, pick one allowed test site and one domain you intend to exclude. Use public, non-sensitive content with distinct facts so you can see which source Copilot is using.

Ask a question that would normally make the excluded site relevant and inspect the citations. Then apply the exclusion, allow time for the configuration to propagate, and repeat the test in a fresh conversation.

The expected result is not “Copilot refuses to answer everything.” It should continue to use permitted web sources when web grounding is enabled.

Keep ownership of the exclusion list

A list of 800 blocked domains that nobody understands is not governance. For each exclusion, record a reason and an owner. Review the list periodically and remove entries that no longer serve a purpose.

Be especially careful with broad parent domains. An exclusion that looks small can remove a large amount of useful content from grounding.

Update — 9 September 2026

Microsoft announced that Domain Exclusion is available again. If you are reading this after the original August rollback, use the current Microsoft documentation rather than assuming the first rollout behaviour still applies.

Final thoughts

Domain Exclusion is a useful middle ground between unrestricted web grounding and switching web grounding off. Treat the domain list as a managed policy, test it with citations, and always check the current rollout state before troubleshooting a missing setting.