When using folders in a standard Shared Drive, Teams Files, or a SharePoint Document Library, it’s best to keep your structure “shallow” – that is with as few folder levels as possible. This keeps the file paths short and makes it easier to navigate to the files you are looking for.

Most file storage options have limitations on how long total file path names can be. Keeping both folder and file names short and using minimal folders will prevent you from running into those limitations.

In addition, below are some rules to help you name folders:

Rule Examples Dos Examples: Don'ts
Use the folder as a grouping for the folders/files within it and name it appropriately

Use a dash between every word

OR

Use no spaces and capitalize the beginning of each word

OR

DON’T use spaces or underscores

With spaces,
Terminated Contracts

Becomes, as part of a URL or file path name:
…/Terminated%20Contracts/….

With underscores (when part of a link),
File_Naming_Convention_201002.docx

Becomes:
File_Naming_Convention_201002.docx

Capitalize every word to make the name more readable
Don’t use ~ " # % & * : < > ? / \ { | }.   Even if the current location you have files stored in may accept these symbols, other locations may not.
Be consistent with abbreviations and only use abbreviations if the full name is well known