This article explains how to find a customer in Xero by using the ContactId or GUID
The GUID will look similar to this: 9e36eea8-3bfc-4d6e-8b08-5b89e55a1012
1. Construct the Xero Contact URL
https://go.xero.com/Contacts/View/{GUID}
Replace {GUID} with the actual customer’s GUID.
e.g. https://go.xero.com/Contacts/View/9e36eea8-3bfc-4d6e-8b08-5b89e55a1012
2. Open the URL
Copy and paste the constructed URL into your browser while logged in to your Xero account.
The browser will take you directly to the profile page of the specified customer.