Bill Pay integrates with QuickBooks Online Essentials, Plus, and Advanced. This fully integrated product lets you pay and track bills from your QuickBooks account and let you send payments international or domestic via ACH or check.
In adding the contact details of a vendor, it can only be done right away in your QuickBooks Online account.
Log in to your QuickBooks Online account and select the Expenses menu.
Under the Vendors tab, select the customer you want to add a phone number and click Edit on the upper right.
In the Vendor Information window, fill in the contact information and click Save.