Microsoft Brings Native Python Support to Windows on Arm PCs

Python 3.15 now runs natively on Windows on Arm devices by default, eliminating the need for x64 emulation for the interpreter. Microsoft announced the change as part of its efforts to improve Python development on Arm-based Windows PCs.

The release also brings Tier 2 CPython support for Windows on Arm, which means the platform receives continuous testing and must meet official release-quality standards.

For developers, this makes it easier to run Python workloads directly on Arm64 hardware, including applications for data analysis, artificial intelligence, and web development.

Python package compatibility reaches 94%

Microsoft reports that, as of September 2026, 94% of the 1,000 most-downloaded projects on the Python Package Index (PyPI) offer either native Windows on Arm packages or platform-independent versions.

The Anaconda repository also provides more than 2,500 packages for Windows on Arm, expanding the tools available to developers working on Arm-based devices.

However, Microsoft cautions that package availability does not guarantee full application compatibility. Some applications rely on native extensions or third-party dependencies that may still require changes or additional testing.

GitHub Actions adds native Windows on Arm runners

GitHub Actions now supports native Windows on Arm runners, allowing developers to build and test Python packages directly on Arm64 hardware instead of relying on emulation.

Developers can use the windows-11-arm and windows-11-vs2026-arm runners in eligible public and private repositories.

These environments allow package maintainers to identify architecture-specific issues, verify compatibility, and publish native Arm64 builds.

Microsoft encourages Python package maintainers to integrate Windows on Arm testing into their GitHub Actions workflows to improve support across the ecosystem.

Developers can still use x64 emulation

Although Python 3.15 defaults to the native Arm64 interpreter, Windows continues to support x64 emulation for applications and dependencies that lack native Arm builds.

This gives developers a way to continue running existing software while transitioning to native packages.

Microsoft recommends checking application dependencies for Arm64 compatibility before migrating, particularly when projects use compiled extensions or platform-specific components.

Microsoft is also improving the Windows 11 out-of-box experience on Arm PCs with a smarter way to install critical updates during setup. Meanwhile, the company has ended security updates for Exchange and Skype for Business servers, while 0patch has released a fix for a critical Windows Server DNS vulnerability affecting older systems.