Microsoft is moving Teams and Microsoft 365 to new web addresses, here is what your IT team needs to do
Both services are redirecting to new cloud.microsoft domains by early October. Businesses need to update firewall and network settings now, or users could lose access.
Key points
- Microsoft 365 and Teams web apps are moving to new web addresses (domains) under the cloud.microsoft name, with full redirects due by early October 2025.
- The Teams move is already underway; Microsoft 365 was added to the rollout in July 2025.
- Businesses that block the new Copilot address for account-control reasons have a supported alternative: Microsoft's TenantRestrictions tool.
- Teams exceptions are available until 31 December 2026, after which Microsoft says no further delays will be granted.
- Organisations that cannot meet the October deadline are advised to contact their Microsoft account representative.
Microsoft is changing the web addresses its customers use to reach two of its most widely used workplace tools. Teams, the video-calling and chat app, is already moving to teams.cloud.microsoft. Microsoft 365, the suite that includes Word, Excel and Outlook on the web, is heading to copilot.cloud.microsoft. Both changes were announced through Microsoft's internal customer notice system in posts MC1465764 and MC1462915.
For most employees, nothing will look different. The browser will redirect them automatically. The headache falls on IT departments.
Why does this matter to businesses?
Corporate networks often filter or block internet addresses through tools called firewalls, proxies, and secure web gateways. Think of these as digital bouncers: they check every destination a device tries to reach and block anything not on the approved list. If the new Microsoft addresses are not on that list, staff will simply lose access to Teams or Microsoft 365 on the web.
Microsoft is asking IT teams to review those approved lists on every device, firewall, and network gateway their organisation runs, and add the new addresses before the redirect completes.
| Service | Old address | New address | Redirect deadline |
|---|---|---|---|
| Microsoft Teams | teams.microsoft.com | teams.cloud.microsoft | Early October 2025 |
| Microsoft 365 | microsoft365.com | copilot.cloud.microsoft | Early October 2025 |
| Teams (exception window) | , | , | 31 December 2026 |
What if we were blocking the Copilot address on purpose?
Some organisations had already blocked copilot.cloud.microsoft to stop staff signing in with personal Microsoft accounts rather than company ones. That is a reasonable policy, and Microsoft acknowledges the conflict. Its answer is to use a feature called TenantRestrictions, a setting that lets a company allow access to the address but limit it only to company-approved accounts. The block-everything approach will no longer be practical once Microsoft 365 moves there.
What should IT teams do right now?
Check your approved-address lists immediately. Microsoft's guidance is to confirm that corporate devices, proxies, firewalls, and web gateways can all reach both new addresses. Organisations that rely on a third-party web gateway should check with that vendor too.
If your network setup cannot be updated before early October, Microsoft says to call your account representative. Limited flexibility exists for Teams until the end of 2026, but after that date Microsoft has been explicit: no extensions.
End users do not need to do anything. If your IT team handles the network changes, the redirect will be invisible. If access to Teams or Microsoft 365 suddenly stops working in a browser, the likely cause is a firewall or gateway that has not yet been updated, and a call to IT is the right first step.
