The reason is to facilitate RECONCILIATION between FI and CO. The sum of all ‘REAL’ assignments in CO should add up to the sum of all expense and revenue postings (where cost/revenue elements have been created for the GL account of course) in FI. A normal expense invoice POSTING to expense accounts / cost elements will be a ‘real’ posting. If the system is displaying an error message insisting on a ‘cost accounting assignment’ and you THINK you have entered one, then possibly you have specified a statistical assignment. A common error is in thinking that the business area will do – Business areas are FI elements not CO elements.

The reason is to facilitate reconciliation between FI and CO. The sum of all ‘real’ assignments in CO should add up to the sum of all expense and revenue postings (where cost/revenue elements have been created for the GL account of course) in FI. A normal expense invoice posting to expense accounts / cost elements will be a ‘real’ posting. If the system is displaying an error message insisting on a ‘cost accounting assignment’ and you think you have entered one, then possibly you have specified a statistical assignment. A common error is in thinking that the business area will do – Business areas are FI elements not CO elements.