I have a supplier who is also a customer but I can't create the company as a customer because they are already a supplier. What is the best way to solve this?

Hello paul20,

Welcome to the Community. I can help you with your question about creating customers and vendors in QuickBooks Online.

You can still use the exact name as a customer, but add additional characters on the Display name section of the profile. For visual reference, I'm adding two screenshots of the vendor and customer I created:

If there's anything I can help you with, let me know by posting your response. I'll be here to provide additional assistance.