brotherton-erpnext/erpnext/docs/user/guides/CRM/contact.md

Contacts and Addresses in ERPNext are stored separately so that you can
attach multiple Contacts or Addresses to Customers and Suppliers.

To create a new Contact go to ,

> CRM > Contact > New

<img class="screenshot" alt="Contact" src="{{url_prefix}}/assets/img/crm/contact.png">

Or you can add a Contact or Address directly from the Customer record, click on “New
Contact” or “New Address”.

<img class="screenshot" alt="Contact" src="{{url_prefix}}/assets/img/crm/contact-from-cust.png">

> Tip: When you select a Customer in any transaction, one Contact and Address
gets pre-selected. This is the “Default Contact or Address”.

To Import multiple Contacts and Addresses from a spreadsheet, use the Data
Import Tool.