For a truly smooth offline installation, don't forget to download and carry the and DirectX End-User Runtimes . Without these, the engine may fail to launch on a fresh Windows installation regardless of how you downloaded the editor.
(like schools or businesses) who have purchased Unreal seats or have an active Unreal Subscription How to Access Log in to the Epic Games Developer Portal Navigate to Epic Tools Unreal Engine in the left menu. Unreal Engine Offline Installer from the "Type" dropdown. Choose version and download. Epic Games Developers Alternative "Offline" Methods download full unreal engine 427 offline installer
Yes. Contact Epic's enterprise support. They provide a direct .zip of the entire engine delivered via Aspera or a physical HDD for a fee. For a truly smooth offline installation, don't forget