Within Teamwork.com, you can add multiple people quickly to your site as users or contacts by importing them in a CSV or vCard format.
Select the People option from your left-hand side nav.

Click the Import button in the top-right corner and choose whether you import users or contacts
Importing users
The option to import people as users. The import must be in a specific format; example files are available once you select the import function. Imported users are not sent an invite email but you can send them one later.

Importing contacts
The option to import people as contacts. The import must be in a specific format; example files are available once you select the import function.

Editing users
You can also use the import function to update existing users and contacts on your site. The sample import file shows which properties are supported, such as name and job title.
- The email address is used as the unique identifier for each person. When you upload an import file, any email addresses in the file that match existing user email addresses on your site will be updated with the associated user properties in the file.
- If you change an email address or user ID in the file, a new user will be created on your site during the import as there is no existing matching user.
- If you are updating both contacts and users, import each group in separate files (sort the user type column in the file to group them before separating into two files.
Note: It is not possible to edit a user type via the import option.
For more information, see: Quickly Inviting Multiple People to Your Site