Yes, in TidyStock, Purchase Order Numbers is Customer Reference Number in the Sales Purchase Order section.
Have a look at similar frequently asked questions or visit our FAQs page for more information
What is the best way to change my Xero invoice settings?
How does TidyBuild integrate with Xero?
Why is my screen freezing, I have to log out and log back in?
Why is the pricing incorrect when creating a new Purchase Order?
How many material items can we have in the Tidy software?