Customer order Origination

[Cocktails]

Hi all 

I'm trying to find a way to track the origin of orders - i.e - we give a code to business x, who in turn gives it to their members. The member places an order which shows the code so we can track it.  

We have numerous businesses we're working with so need to be able to see which orders are coming from which business code...

Can anyone help?

Thanks

Ginette