For organizations that started with LTSC 2019 but need a newer Office, Office LTSC 2021 is supported on Windows 10 LTSC 2019 (with the latest cumulative updates applied). This extends your Office lifecycle to 2026.

Without Software Assurance or an equivalent subscription, you cannot legally run LTSC.

And then there was Office. Not Microsoft 365. Not the cloud-rotted subscription ghost. Real Office. The kind that lives on a hard drive and asks nothing of tomorrow. Word opened like a clean sheet of paper in 2003. Excel calculated without phoning home. Outlook—well, Outlook still hated everyone, but at least it hated them offline.

. It is often paired with Office LTSC, a perpetual (non-subscription) version of the productivity suite designed for similar "fixed-function" environments. Microsoft Learn Windows 10 Enterprise 2019 LTSC Overview