Storing Payment Reference in UBL

Dear guys/gals

I am new to UBL and its implementation for invoices.

Would like to clarify if my understanding of the below elements usage is correct or not.

Invoice/ PaymentMeans / PaymentID 

I am working on an ERP system which needs to create/read UBL formatted invoices (purchase and Sales).

and i was wondering where i can put my payment reference information. From the UBL specification website (

it seems that the only suitable place is to put it in "Invoice/ PaymentMeans / PaymentID".

Currently in my client company, they have a legacy system which also creates/read UBL formatted invoices, but they are reading and writting it to 

Invoice/ PaymentMeans/ InstructionNote/

Invoice/ PaymentTerms/ Note

Will it cause any problems, if we stored the Payments Reference there?

Or is it a hard rule , that payment reference needs to be stored in "Invoice/ PaymentMeans / PaymentID" only? 


Am i correct to think that, we can put the payment reference in any elements in the UBL, as long the receiving system can identify from the elements it is a paymente reference.

For example: If system X get Payment Reference from "Invoice/ PaymentMeans / PaymentID", when reading my client company legacy UBL, they wont get the payment reference.


This brings me to my next question, does all UBL implementor uses "Invoice/ PaymentMeans / PaymentID" to store payment reference?


Thank you in advance

Your reply is greatly appreaciated.


Except for the cardinality and order of elements dictated by the schema, there are no other "hard rules" in UBL.  Certainly there are common practices that users of UBL employ based on common accounting principles.

A "UBL Customization" specifies the use of optional UBL elements for a given community. Whomever received your UBL invoice will be looking for information where they have planned to look for it.  That may include an "if not here then there" rule, but I doubt it ... I expect all customizations would have an unambiguous specification of where to find information.

My gut feel is that the information you've described would be lost on your recipients.

When you ask "do all implementors do (anything)...", a better place to ask such a question (and your other questions) is UBL-Dev.  Please see the instructions at the top of

I hope this helps.

. . . . . . . . Ken

I am reminded (thanks, Kenneth!) that the conformance clauses of UBL include a set of additional document constraints in addition to the schema expressions.

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