In 'Customers/Customers settings/Update: Customers' you can update your customer data in bulk with a spreadsheet file (CSV, XLS...).

The import file to update your products data has 2 columns:

• the first column with the customer ID, or the customer email, or the customer EAN code,
• the second column with the data to update (emaill, or customer note, …).

When you import the file, you must select the field labels for each column.