diff --git a/include/XMLDocument/invoiceubl21.class.php b/include/XMLDocument/invoiceubl21.class.php
index 58a2a7f9d..40f5bb12e 100644
--- a/include/XMLDocument/invoiceubl21.class.php
+++ b/include/XMLDocument/invoiceubl21.class.php
@@ -54,6 +54,7 @@ class InvoiceUBL21 extends XMLInvoice {
         , 'MY_CITY'
         , 'MY_TVA'
         , 'INVOICE_EMAIL_COMPANY'
+        ,'COMPANY_PEPPOL_ID'
         ];
     protected $pdf_filename; //!< PDF file to insert into XML,
                              //       it is the file on the filesystem