Summary
Microsoft reminds administrators that Internet Explorer mode in Microsoft Edge remains supported through at least the end of 2029. Because modernization projects for legacy applications often take years, organizations relying on this feature should start planning migrations now. No immediate changes occur to your current tenant configuration. Review dependencies early to prevent future business disruption.
Administrator impact: Inventory your legacy web applications and plan modernization projects before support ends.
End user impact: No direct end user impact is expected.
Score rationale: This is a long term planning reminder for legacy applications with no immediate functional change.
Microsoft App Assure App Compatibility Support Microsoft 365 | Lifecycle FAQ Internet Explorer and Microsoft Edge Microsoft Learn
IE mode in Microsoft Edge is supported through at least the end of 2029. Organizations using it should inventory dependencies, assess modernization options, and plan migrations early to avoid disruption. No immediate action is required if IE mode is not used. Microsoft offers free App Assure support for compatibility issues.
Published: 17 Sept 2026
Expires: 31 Jan 2030
Last updated: 18 Sept 2026
Category: Plan for change
Tags: Microsoft 365 suite, User impact, Admin impact
Microsoft Message
Internet Explorer (IE) mode in Microsoft Edge remains supported through at least the end of 2029, as first announced in 2021. Microsoft is sharing this reminder so admins can plan migrations for legacy websites and applications that still depend on IE mode. Application modernization projects can take years to complete depending on the number and complexity of dependencies, so early planning reduces the risk of disruption later.
Rollout schedule
This is a reminder, not a rollout of a new feature or capability. IE mode support continues through at least the end of 2029 across Worldwide, GCC, GCC High, and DoD environments. Microsoft will provide at least one year of notice before retiring IE mode.
Impact on your organization
Who is affected
- Organizations that use IE mode in Microsoft Edge for legacy websites or applications
- Organizations that do not use IE mode are not affected.
Platforms and services
Microsoft Edge
What will happen
- If your organization does not use IE mode, there is no impact and no action is required.
- If your organization uses IE mode, you can continue using it while you modernize affected websites and applications.
- Support for IE mode continues through at least the end of 2029, but modernization projects may take years to complete.
- This message does not change your current IE mode configuration or require you to disable IE mode immediately. It is intended to help you identify dependencies and plan migration work before the end of the current support period.
Action required and recommendations
If your organization no longer uses IE mode in Microsoft Edge, no action is required.
If your organization still depends on IE mode:
- Inventory your IE mode dependencies. Identify the business-critical websites and applications that still require IE mode. Review your existing Enterprise Mode Site List and current usage to build your inventory.
- Assess modernization options. Determine whether each application should be updated, rehosted, replaced, or rebuilt using modern technologies and services.
- Request assistance if needed. Microsoft App Assure provides no cost assistance for eligible customers experiencing application compatibility issues with Microsoft Edge and IE mode.
Planning early can help your organization identify migration risks and reduce the likelihood of disruption as you move away from IE mode dependencies.
Learn more
- Microsoft App Assure: App Compatibility Support | Microsoft 365
- Lifecycle FAQ – Internet Explorer and Microsoft Edge | Microsoft Learn
Compliance considerations
No compliance considerations identified, review as appropriate for your organization.