A customer is an individual or business who buys products and services (i.e items) from a business.
Users add customers into QuickBooks Online so they can quickly associate them with invoices, sales receipts, and other sales forms.
Learn more about how QuickBooks Online users add and manage customers.
Your app needs to be able to link customers to specific transactions such as invoices, sales receipts, and refunds. These require customer data so QuickBooks knows who to associate the info with.
Design your app so it can track your end-user’s existing customers and vendors.
Customers and vendors may already exist in a user’s QuickBooks Online company. It’s important to look them up before creating a new object to avoid errors.
AccountingInfoPrefs.CustomerTerminologyattribute of the Preferences endpoint to see how users define their “customers” or “vendors,”