Mandatory parameter.

It consists of 6 numeric characters and must be unique for each transaction for a given shop on the same day.

Note: the uniqueness of the transaction identifier is based on the universal time (UTC).

The merchant website must guarantee this uniqueness during same the day. It must be between 000000 and 899999.

The numbers between 900000 and 999999 are reserved for refunds and operations made via the Expert Back Office.

Input and output field, returned in the response (IPN and Return URL).

Format n6
Error code 03

Common errors:

The form is rejected:
  • if the transmitted value contains less than 6 digits
  • if the value is null
  • if the field is absent
  • if an identical transaction number has already been sent on the same day.
    If the buyer clicks on "Cancel and return to the shop", the transaction number must be different for the next attempt as the previous one will be considered as already used.

    Otherwise, the message "The transaction has been canceled" will appear.

Category Transaction details.