Configuring Tax Number Check for Business Partner

1. Define Tax Number Categories

Configure tax number categories in SAP Central Business Configuration. These categories are required when adding tax numbers to business partner master data and will be referenced in our custom validation. We do this with the configuration activity Define Tax Number Categories (104758).

2. Create Custom Code List

Set up error messages in the Custom Reusable Elements app:

Code	Descriptions
001	Tax number must start with 'C' or 'I'
002	Tax number must be 12 characters long
003	Characters 2-12 must be numerical digits

3. Create Custom Logic Implementation

Build the validation implementation using the "Custom Logic" app. The implementation will:

• Reference the configured tax number category
• Use the custom code list for error messages
• Validate tax numbers against the defined rules

For the implementation the following code will be used.

Code Snippet

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DATA ls_message LIKE LINE OF ct_validationmessage.
DATA ls_tax_num LIKE LINE OF it_bp_tax_num.
DATA lv_digits TYPE string VALUE '0123456789'.
DATA lv_message TYPE string.
DATA: lv_len_tax TYPE i, lv_tax_digits TYPE string.

LOOP AT it_bp_tax_num INTO ls_tax_num.
"Validate tax number type for Malives
 IF ls_tax_num-bptaxtype = '9MV1' OR ls_tax_num-bptaxtypeforedit = '9MV1'.

* Check first character of the tax number
  IF ls_tax_num-bptaxnumber(1) <> 'C' AND ls_tax_num-bptaxnumber(1) <> 'I'.
     CLEAR lv_message.
     SELECT SINGLE FROM YY1_MV_MESSAGE FIELDS description
        WHERE code = '001' INTO @lv_message.
     IF sy-subrc = 0.
         ls_message-msgv1 = lv_message.
         ls_message-msgty = 'E'.
         APPEND ls_message TO ct_validationmessage.
     ENDIF.
  ELSE.
* Check the total length of the tax number
      lv_len_tax = STRLEN( ls_tax_num-bptaxnumber ).
      IF lv_len_tax <> 12.
          CLEAR lv_message.
          SELECT SINGLE FROM YY1_MV_MESSAGE FIELDS description
             WHERE code = '002' INTO @lv_message.
          IF sy-subrc = 0.
              ls_message-msgv1 = lv_message..
              ls_message-msgty = 'E'.
              APPEND ls_message TO ct_validationmessage.
          ENDIF.
      ELSE.
* Check that positions 2 - 12 are numerical characters only
      lv_tax_digits = ls_tax_num-bptaxnumber+1.
      IF NOT lv_tax_digits CO lv_digits.
          CLEAR lv_message.
          SELECT SINGLE FROM YY1_MV_MESSAGE FIELDS description
             WHERE code = '003' INTO @lv_message.
          IF sy-subrc = 0.
              ls_message-msgv1 = lv_message.
              ls_message-msgty = 'E'.
              APPEND ls_message TO ct_validationmessage.
          ENDIF.
      ENDIF.
  ENDIF.
  ENDIF.
   ENDIF.
  ENDLOOP.

Note

When reusing this implementation, update both the Tax Number Category ID and Custom Code List to match your configuration.

In the following simulation, we'll walk through each step in detail and test the validation to ensure it works correctly.