This functionality is only available in the 2.6 versions of GnuCash and is only loaded by default for versions greater than 2.6.

For versions lower than 2.6 the Customers and Vendors importer is an optional module and needs to enabled by editing the file $HOME/.gnucash/config.user, adding the line:

(gnc:module-load "gnucash/plugins/customer_import" 0)

On Linux systems this file is found at $HOME/.gnucash/config.user and on macOS it is ~/Library/Application Support/Gnucash/config.user. If the file doesn’t already exist you will have to create it. After restarting GnuCash the item will appear at the bottom of the business menu.

In order for the importer to work each line in the input file must have the following structure.

id, company, name, addr1, addr2, addr3, addr4, phone, fax, email, notes, shipname, shipaddr1, shipaddr2, shipaddr3, shipaddr4, shiphone, shipfax, shipmail

Fields can be separated with commas or semicolons and each field can be in quotes. These options are selectable in the import dialog. Vendors don’t have shipping information so even though the fields have to exist, leave them empty. The id field is optional and if it is empty a new id will be chosen. If the id field has a value this will UPDATE any vendor/customer with the same id. This may not be what you want. Note that in your input file the data must be a single line for each customer/vendor.

The importer does not currently import billing information for customers or vendors, these will have to be edited individually after importing.