# FX-SCH-A-000122

Source: https://xmlvalid.com/rules/FX-SCH-A-000122

> Amount due for payment (BT-115) = Invoice total amount with VAT (BT-112) -Paid amount (BT-113) +Rounding amount (BT-114).

- Level: error
- Rule sets: Factur-X BASIC rules 1.09
- Context: `//ram:SpecifiedTradeSettlementHeaderMonetarySummation`
- Test: `(xs:decimal(ram:DuePayableAmount[1]) = xs:decimal(ram:GrandTotalAmount[1]) - xs:decimal(ram:TotalPrepaidAmount[1]) + xs:decimal(ram:RoundingAmount[1])) or ((xs:decimal(ram:DuePayableAmount[1]) = xs:decimal(ram:GrandTotalAmount[1]) + xs:decimal(ram:RoundingAmount[1])) and not(ram:TotalPrepaidAmount)) or ((xs:decimal(ram:DuePayableAmount[1]) = xs:decimal(ram:GrandTotalAmount[1]) - xs:decimal(ram:TotalPrepaidAmount[1])) and not(ram:RoundingAmount)) or ((xs:decimal(ram:DuePayableAmount[1]) = xs:decimal(ram:GrandTotalAmount[1])) and not(ram:TotalPrepaidAmount) and not(ram:RoundingAmount))`

Validate a document against these rules: https://xmlvalid.com/validate