Our detects password.excel
Sends us an email, we have to tell the client to fuck it off because it’s dumb
Best Practice?
Move all of the passwords in your stupid spreadsheet to a password manager, we use 1password and we like it?
Oh? Don’t want to do that?
What? 1Password costs money and you’re not down for that? Fine
The barely acceptable alternative
Change the filename to not have ‘password’ it in, and password protect it.
File > Info > Protect Workbook > Encrypt with Password > Set a password

Write that fucker down
There is no ‘forgot my password’ for this, you forget it and data is gone.
Do NOT write it down in a new passwords.excel spreadsheet
Yes that has actually happened.