How do I find the client number

Good day, @carol11.

I'll be more than happy to help you obtain the information you're looking for. Can you clarify what exactly you mean by client number? QuickBooks Online companies, clients and firms alike, do have an identification number used for referencing to support. Finding that ID number is a breeze, just follow these steps:

Finding your client's Company ID

1. From your QuickBooks Online Accounting firm, navigate to the client company from the dropdown (▼) menu at the top.
2. While on the client's Dashboard, press CTRL+ALT+? (the question mark button on your keyboard).
3. The Company ID will appear in a pop-up in the center of the screen. If you'd like, make a personal note of it for future reference.

I'm including a screenshot displaying what this pop-up looks like in our sample company:

This enables you to access the company ID for whichever client you need. If there's something else you need to find, please don't hesitate to let me know, I'm always available here for all of your QuickBooks questions. Thanks for dropping in, I'll keep an eye out for your response.

When an invoice is created for a Client/Customer, there is a box called "Client Number".  Does this number have to be manually entered each time an Invoice is created for a client?  Or is there a place in the Client/Customer setup where this information is entered so it is stored? 

Hi @sfvaughan,Currently, we're unable to auto-populate the Client Number information on customer invoices. If you want to copy this information when billing clients, you'll need to do it manually.Follow these steps to add a custom section on a sales form template:

1. From the QBO Dashboard, click on the + New button.
2. Select Invoice from the list.
3. Before filling out the information, click the Gear icon found at the top-right section of the form.
4. Click on the Add another field link.
5. On the blank field, add the description Client Number.
6. Tap the X button to exit.
7. You will then see this option on the invoice. Manually input the number you want.
8. You only need to do this step once, the  Client Number field will automatically apply to all invoices.

 
For other basic invoice customizations, see this article: How to Customize Invoices in QuickBooks Online?
 
Let me know if there's anything else I can help you with QuickBooks. I'm always here to provide further assistance. Have a nice day!