I have 2 organizations and want to merge expenses from both in one table

I have 2 organizations and want to merge expenses from both in one table

Hello,

I merged Expense Tables from 2 organizations using UNION ALL functions. However, I want to see which rows are from which organization. How do I do? This is my SQL query:
SELECT
             Account ID","Expense Category","Expense ID","Total (BCY)","Created Time"
FROM  "Expense Item" 
UNION ALL
SELECT
            Account ID","Expense Category","Expense ID","Total (BCY)","Created Time"
FROM  "Expense Item (Zoho Books)"
 
Thank you very much!