Microsoft will add Anthropic models to Office 365 Copilot in a move that aims to raise the quality of advanced tasks inside Word, Excel, PowerPoint, and Outlook. The company will blend Anthropic’s Claude models with existing OpenAI models to power specific features while keeping the overall Copilot product and pricing unchanged.
Microsoft’s internal testing found Anthropic’s latest Claude Sonnet 4 performs especially well on tasks such as automating complex financial functions in Excel and creating full slide decks in PowerPoint from brief prompts. This performance advantage has driven the decision to add Anthropic models for targeted workloads.
To access Anthropic models, Microsoft will pay Amazon Web Services because Anthropic hosts its models on AWS. The company will continue to use OpenAI models for many Copilot features and will maintain its long-term partnership with OpenAI. Microsoft expects to announce the change in the coming weeks.
The integration reflects a broader multimodel strategy at Microsoft. The company has already used Anthropic models in GitHub Copilot and has built its own model and infrastructure to support enterprise needs. This approach gives Microsoft flexibility to choose the best model for each task and to reduce dependency on a single provider.
Microsoft has not changed Copilot pricing in this plan. The company will keep Copilot at the current subscription price for users while it layers in Anthropic technology for selected features. Analysts estimate Copilot-related offerings are already generating significant revenue and adoption within Microsoft’s customer bases.
For customers, the change should mean better output on specific high-value tasks. For example, financial analysts who rely on Excel automation may see more reliable spreadsheet generation, and accountants may benefit from improved formula handling. Business users who create decks will likely get stronger first drafts that require less manual cleanup. The shift is designed to make Copilot more useful in daily work without changing how customers buy the product.
There are tradeoffs. Microsoft will pay AWS to access Anthropic models even as it retains preferential access to OpenAI models through its investment. The move adds operating cos,t but Microsoft appears willing to accept this to reach quality goals and to keep enterprise customers satisfied. It also signals increased competition among model providers and a market in which large cloud vendors and AI firms each play strategic roles.
It also highlights a shift in enterprise AI where choice and model fit matter more than exclusive partnerships.