MC1176368 – (Updated) GPT-5 becomes the default Copilot model

Product:

Copilot, Microsoft 365 Apps, Microsoft 365 Copilot, Teams

Platform:

Online, Web, World tenant

Status:

Change type:

New feature, Updated message, User impact

Links:

Details:

Summary:
GPT-5 will become the default Microsoft 365 Copilot model in a phased rollout from early to late November 2025. Initially, users can toggle GPT-5 on or off; later, it becomes mandatory with no opt-out. GPT-5 offers faster, more accurate responses with dynamic model routing and deeper reasoning.

Details:
Updated October 30, 2025: We have updated the timeline. Thank you for your patience.
[Introduction]
We're updating the default experience for users with the Microsoft 365 Copilot license by introducing GPT-5 as the standard model. GPT-5 is OpenAI's most advanced language model, designed to deliver faster, more accurate, and more context-aware responses. It features dynamic model routing, which automatically selects the best-performing variant for each prompt-using high-throughput models for quick replies and deeper reasoning models for complex tasks. This change simplifies the user experience and enhances performance across all Copilot endpoints.
[When this will happen:]
General Availability (Worldwide): Phased rollout begins early November 2025 (previously late October) and completes by late November 2025.

Change Category:
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Scope:
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Release Phase:

Created:
2025-10-21

updated:
2025-10-30

Task Type

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Docu to Check

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MS How does it affect me

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MS Preperations

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MS Urgency

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MS workload name

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Pictures

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summary for non-techies**

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Direct effects for Operations**

User Experience Degradation
If users are not prepared for the transition to GPT-5, they may experience confusion and frustration due to the removal of the toggle option in Phase 2, leading to a lack of control over their interactions with the AI.
   - roles: End Users, Helpdesk Support
   - references: https://www.microsoft.com/en-us/microsoft-365/blog/2025/10/30/introducing-gpt-5-as-the-default-copilot-model/

Increased Support Tickets
The change to GPT-5 without adequate preparation may lead to an increase in support tickets as users encounter issues or have questions about the new features and functionalities, overwhelming helpdesk resources.
   - roles: Helpdesk Support, IT Operations
   - references: https://www.microsoft.com/en-us/microsoft-365/blog/2025/10/30/introducing-gpt-5-as-the-default-copilot-model/

Training Material Obsolescence
Existing training materials may become outdated or irrelevant, leading to user errors and inefficiencies as users rely on old information that does not reflect the new capabilities of GPT-5.
   - roles: Training Coordinators, End Users
   - references: https://www.microsoft.com/en-us/microsoft-365/blog/2025/10/30/introducing-gpt-5-as-the-default-copilot-model/

Configutation Options**

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Opportunities**

Enhanced User Training and Support
With the introduction of GPT-5, users may require additional training to fully leverage its capabilities. Creating targeted training sessions and support materials can enhance user experience and productivity, ensuring that users are aware of how to utilize the new features effectively.
   - next-steps: Develop a training program that includes webinars, video tutorials, and updated documentation focused on GPT-5 features and best practices. Schedule sessions before and after the rollout to accommodate all users.
   - roles: IT Support, Training Coordinators, Team Leaders
   - references: https://techcommunity.microsoft.com/t5/microsoft-365-blog/introducing-microsoft-365-copilot-a-new-way-to-work/ba-p/3284344

Improved Helpdesk Efficiency
The transition to GPT-5 may lead to an increase in helpdesk inquiries as users adjust to the new system. By equipping helpdesk teams with comprehensive knowledge and resources about GPT-5, response times and issue resolution can be improved.
   - next-steps: Create a detailed FAQ and troubleshooting guide specifically for GPT-5 features. Train helpdesk staff on common issues and solutions related to the new model to ensure they can assist users effectively.
   - roles: Helpdesk Staff, IT Managers, Operations Managers
   - references: https://www.microsoft.com/en-us/microsoft-365/blog/2023/05/05/microsoft-365-copilot-what-you-need-to-know/

Data Utilization and Reporting Enhancements
The introduction of dynamic model routing in GPT-5 allows for better data utilization. IT can leverage usage data to analyze user interaction patterns and improve service delivery based on real user needs.
   - next-steps: Implement analytics tools to monitor how users interact with GPT-5. Use this data to generate reports that can inform future IT strategies and service improvements.
   - roles: Data Analysts, IT Managers, Product Managers
   - references: https://www.forbes.com/sites/bernardmarr/2023/06/12/how-ai-is-transforming-business-intelligence-and-data-analytics/?sh=78e2a84b26b2

Potentional Risks**

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Data Protection**

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IT Security**

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Hypothetical Work Council Statement**

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DPIA Draft**

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explanation for non-techies**

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