# BT-106 — Sum of Invoice line net amount

> https://billhorse.com/en/terms/bt-106/

Sum of all line net amounts (BT-131). Mandatory — and it must exactly equal the actual sum of the lines; compute it rather than maintaining it separately.

## Where does it live in the XML?

- UBL: `cac:LegalMonetaryTotal/cbc:LineExtensionAmount`
- CII: `rsm:SupplyChainTradeTransaction/ram:ApplicableHeaderTradeSettlement/ram:SpecifiedTradeSettlementHeaderMonetarySummation/ram:LineTotalAmount`

## Checked by these rules

- [BR-12 — Sum of line amounts missing](https://billhorse.com/en/rules/br-12/)
- [BR-CO-10 — Line total mismatch](https://billhorse.com/en/rules/br-co-10/)
- [BR-CO-13 — Net total inconsistent](https://billhorse.com/en/rules/br-co-13/)