Five recurring patterns
Where risks tend to linger
1. Outdated condition records that are still formally active
In many environments, old records remain in place because nobody is confident they are no longer being hit. This creates overlap, unintended priority or logic that only surfaces in specific combinations. The error is not in any single table, but in the totality of records that have been built up over the years.
2. Master data that makes the correct VAT outcome impossible
Incomplete customer or vendor data, incorrect country codes, inconsistent material classifications or missing indicators mean that even a reasonable tax procedure produces a weak outcome. The system then gets corrected at output level, while the problem actually sits in the input.
3. Local workarounds outside SAP that were never reflected back
Many teams resolve exceptions pragmatically outside the system. That helps in the short term, but makes it harder later to determine which situations should be structurally reconfigured. The risk is that operational reality no longer matches the system logic.
4. Change management without VAT regression testing
A release or transport does not need to be VAT-related to have a VAT effect. Changes to pricing, master data, order flows or intercompany processes can unintentionally feed through into tax determination. Without a fixed regression test, that often only becomes visible during the filing period.
5. Insufficient documentation of deliberate exceptions
Some exceptions are perfectly justified. But if there is no record of why a deviation exists, who accepted it and when it should be reassessed, you end up with a black box. That makes review, handover and audit unnecessarily difficult.
