Microsoft does not provide a direct, official "ISO" file for Microsoft 365 in the traditional sense, as it is primarily a cloud-based service. Instead, users can access an offline installer (often in .img format, which is functionally equivalent to an ISO) or use the Office Deployment Tool (ODT) to create a local installation source. Methods to Obtain an Offline Installer
If you have a Volume License for Office 2019 or 2021 (LTSC), you absolutely can download an ISO from the Microsoft VLSC. However, if you have a Microsoft 365 subscription, you cannot. ms office 365 iso
It is vital to distinguish between the services. If you absolutely need an ISO file for compliance or air-gapped systems, you do not want Microsoft 365. You want Office LTSC (Long Term Servicing Channel) . Microsoft does not provide a direct, official "ISO"
If you’ve recently searched for a way to install Microsoft Office 365, you’ve probably typed the phrase "MS Office 365 ISO" into Google. There is no official consumer “Microsoft 365 ISO”
📍 Note: Once installed, you must connect to the internet at least once every 30 days to keep your subscription active.