The short answer
No. Your data. Shrink it from its app; don’t delete the folder.
What is it?
The Spotlight search index for your startup disk, stored in /System/Volumes/Data/.Spotlight-V100. It lets Spotlight, Finder search and Mail find files and their contents instantly. It is usually a few GB; far more than that can mean a damaged index or folders full of many small files being indexed.
The search index. If it is unusually large, rebuild it by adding and removing your disk in Spotlight privacy settings.
What happens if you delete it?
macOS rebuilds the index automatically. A full rebuild can take hours, and search results are incomplete meanwhile.
How to remove it properly
Do not delete it manually; it is protected by macOS. To rebuild an oversized index, open System Settings › Spotlight, click Search Privacy, add your disk, wait a few seconds, then remove it from the list. To keep it smaller, add folders you never search, such as virtual machines or build folders, to the same list.
Don’t remove it by hand; macOS manages it.
How MoreRoom helps
MoreRoom recognises this as your data and never suggests deleting it. It shows how much space it takes, so you can shrink it from its own app.
Frequently asked questions
Can I delete the .Spotlight-V100 index folder?
No. Your data. Shrink it from its app; don’t delete the folder. macOS rebuilds the index automatically. A full rebuild can take hours, and search results are incomplete meanwhile.
Will Spotlight index come back after I delete it?
Yes. macOS rebuilds the index automatically. A full rebuild can take hours, and search results are incomplete meanwhile.
How do I remove Spotlight index properly?
Do not delete it manually; it is protected by macOS. To rebuild an oversized index, open System Settings › Spotlight, click Search Privacy, add your disk, wait a few seconds, then remove it from the list. To keep it smaller, add folders you never search, such as virtual machines or build folders, to the same list.