Microsoft distributes this runtime through a main meta-package and several architecture-specific child packages to reduce final app size: Microsoft.ICU.ICU4C.Runtime.win-x64 72.1.0.3 - NuGet
Around 2018–2019, Microsoft began a significant shift: . This was driven by: microsoft.icu.icu4c.runtime
You don't typically install this package manually. It comes as a when you build certain types of projects. : The package includes the common , i18n
With .NET Native AOT (ahead-of-time compilation), the runtime does not include a JIT or a full ICU—so the package or a minimal ICU subset is still required for globalization. Expect this package to remain a fundamental piece of cross-platform .NET for years to come. : The package includes the common
It contains the precompiled (DLLs) of the ICU4C library, specifically built and maintained by Microsoft.
: The package includes the common , i18n (internationalization), and data libraries from the Microsoft-modified MS-ICU repository .
. If you aren't on .NET Core/.NET 5+, you'll need to look at alternative wrappers like Final Verdict