Yes, this behavior is correct in current versions of Excel when AutoSave is on and the file is stored in OneDrive, OneDrive for Business, or SharePoint.
In this scenario:
- AutoSave saves changes automatically every few seconds to the same file.
- Because the file is being updated continuously, Excel no longer prompts to confirm overwriting; it just updates the existing document.
- The classic File > Save As flow is effectively replaced by File > Save a Copy when working with cloud files. To avoid overwriting the original, use File > Save a Copy before making changes and work in that copy instead.
- Manual saving (Ctrl+S or File > Save) is still available, but with AutoSave on, it typically just commits the current state to the same file without an overwrite prompt.
If the goal is to keep the original unchanged, the recommended pattern is:
- Open the original file.
- Use File > Save a Copy.
- Edit the new copy (AutoSave will then apply to that copy).
If AutoSave is not visible or not enabled, Excel still supports manual saving with File > Save or File > Save As, but the overwrite confirmation prompt is not described in the provided documentation and is no longer the primary workflow for cloud-backed files.
References: