Interface – Send a customer invoice with Custom Fields Using IDOC

April 6, 2026
Kishore Thutaram
ABAP
0

Introduction

In real-world SAP integrations, sending standard invoice data is often not enough. Outbound IDOCs for external systems often require businesses to include additional custom fields.

In this guide, we’ll walk through how to send a customer invoice with custom fields using an IDOC extension, using real-time techniques followed in SAP projects.

Business Scenario

A company needs to send invoice data to an external system, but standard IDOC segments do not include the following:

Custom material attributes
Additional business-specific fields
Enhanced item-level data

Because of this:

External systems lack the required data
Manual mapping becomes complex
Integration fails or becomes inefficient

This requires extending the IDOC structure with custom segments and fields.

Solution Overview

We solve this using:

IDOC Extension (WE30 / WE31)
User Exit implementation
Custom segment population logic

What this solution does:

Enhances standard invoice IDOC
Adds custom fields dynamically
Ensures seamless outbound integration

Step 1: Maintain Partner Profile (WE20)

Configure outbound parameters for the invoice message type.

This ensures IDOC is triggered correctly.

Step 2: Create IDOC Extension (WE30 / WE31)

Create a custom segment (e.g., ZZINVITM)
Add required custom fields

If you’re new to IDOC structure and segments, understanding the data flow is important — refer to your guide on handling integrations, such as receiving sales orders via IDOC, which clearly explains the segment hierarchy.

Step 3: Find and Implement User Exit

Use:

Function Module: EXIT_SAPLVEDF_002
Exit: EXIT_SAPLV56K_002
Include: ZXEDFU02

This is where custom logic is written.

If you’re unsure how to debug exits and enhancement logic, it’s worth checking your guide on debugging ABAP programs effectively to trace IDOC processing step-by-step.

Step 4: Populate Custom Segment Data

SELECT matnr, zz_mchl1, zz_mchl2, zz_mchl3 
FROM mara 
INTO TABLE @DATA(lt_zzinvitm)
FOR ALL ENTRIES IN @lt_xtvbdpr 
WHERE matnr = @lt_xtvbdpr-matnr.

LOOP AT int_edidd ASSIGNING <fs_edidd> WHERE segnam = 'E1EDP01'.

lv_index = sy-tabix + 1.

DATA(ls_custom_seg) = VALUE #( int_edidd[ lv_index ] OPTIONAL ).

IF is_int_edidd-segnam = 'E1EDP19' AND ls_custom_seg-segnam <> 'ZZINVITM'.

ls_e1edp19 = is_int_edidd-sdata.

DATA(ls_xtvbdpr1) = VALUE #( xtvbdpr[ matnr = ls_e1edp19-idtnr ] OPTIONAL ).

IF ls_xtvbdpr1 IS NOT INITIAL.

DATA(ls_zzinvitm) = VALUE #( lt_zzinvitm[ matnr = ls_e1edp19-idtnr ] OPTIONAL ).

IF ls_zzinvitm IS NOT INITIAL.

ls_edidd-segnam = 'ZZINVITM'.
ls_edidd-psgnum = 'E1EDP01'.

ls_edidd-sdata = VALUE zzinvitm(
zzmchl1 = ls_zzinvitm-zz_mchl1
zzmchl2 = ls_zzinvitm-zz_mchl2
zzmchl3 = ls_zzinvitm-zz_mchl3
).

INSERT ls_edidd INTO int_edidd INDEX lv_index.

ENDIF.
ENDIF.
ENDIF.

ENDLOOP.

Step 5: Test Output (WE02)

Execute invoice output
Check IDOC in WE02
Verify custom segment data

If performance issues occur while processing large IDOCs, follow best practices from your ABAP performance tuning techniques guide to optimize data handling.