Uninstall BILL OS and keep your data

1. Open Windows Settings → Apps, find BILL OS and choose Uninstall.
2. Confirm that you want to uninstall.
3. Choose what happens to your business data: Keep my business data (the default), or remove it, which asks for a second confirmation.

Reinstalling later finds kept data as it was. Only BILL OS’s own data folder is ever removed, and only when you choose to remove it.

For IT: /S uninstalls silently and keeps the data; /S /PURGE removes it.