Bulk import of users in WordPress can be done by WordPress Users and WooCommerce Customers Import Export Plugin. If you have the details of the users in a CSV file, then it is really easy to import all the user data from the CSV file to the WordPress website. You can visit the product page of the plugin to know more details about the plugin.
If you do not have the CSV file prepared, you can use the same plugin to export the data to a CSV file. Or you can use a spreadsheet program of your choice, enter the data, and then save the file with the .csv extension. Also, the CSV Import file must be in UTF-8 format. For more information about UTF-8 encoding, read How to save CSV / Excel File as UTF-8 Encoded?
There are different methods with which you can import the users into the WordPress site. These methods depend on the location of the CSV file. This is what the import page of the plugin looks like.
Method 1: Import the file saved locally on the computer
In this method, you can upload the CSV file that is saved locally on the computer, and then the plugin will import the users and the user data in the CSV into the WordPress site/WooCommerce store.
Method 2: Use FTP to import the CSV file located on the server
If the CSV file is located on a remote server, you can download the CSV file from the server by giving the FTP credentials of the server. If you wish, you can also use FTPS, an extension of the FTP. After you have given the FTP details then you can test the FTP connection and then import the file from the server.
After you have selected the method of importing, the next step is to map the file to the WordPress user data fields. This is to ensure that the right data are imported into the right data fields. After all the fields of the CSV file have been mapped the next step is to import the files.
This will import the users in bulk into the WordPress website.
Now, if you need to fix/update the data in the CSV in bulk during the import, you can do so using the evaluation field while mapping. This field can be used to apply rules that can modify all the data in an entire row.
You can also update the existing users in bulk using WordPress Users and WooCommerce Customers Import Export Plugin. If you have an updated CSV with new information about the existing users on the website, then you can import the CSV so that the new information is applied to the existing users in the CSV.
To do that all you need to do is click on the Update Users if exists checkbox. This will open the Merge Users.
The rest of the process is the same as importing the CSV file without updating the existing users.