# BR-27

Source: https://xmlvalid.com/rules/BR-27

> The Item net price (BT-146) shall NOT be negative.

- Level: error
- Rule sets: EN 16931 rules (UBL) 1.3.17, EN 16931 rules 1.3.16 (UBL)
- Context: `cac:InvoiceLine | cac:CreditNoteLine`
- Test: `(cac:Price/cbc:PriceAmount) >= 0`

> The Item net price (BT-146) shall NOT be negative.

- Level: error
- Rule sets: EN 16931 rules (CII) 1.3.17, EN 16931 rules 1.3.16 (CII), Factur-X EN 16931 rules 1.09.2
- Context: `//ram:IncludedSupplyChainTradeLineItem`
- Test: `(ram:SpecifiedLineTradeAgreement/ram:NetPriceProductTradePrice/ram:ChargeAmount) >= 0`

> Preţul net al articolului (BT-146) trebuie să NU fie negativ. #The Item net price (BT-146) shall NOT be negative. (… = '…')

- Level: error
- Rule sets: Romanian RO e-Factura rules (UBL) 1.0.9
- Context: `cbc:PriceAmount`
- Test: `(.) >=0`

## Why it fails

- A line has a negative price, often to show a discount or a returned item.

## How to fix it

- Keep prices positive. Make the quantity negative for a returned item (the line amount then comes out negative), or give a discount as an allowance on the line or the document.

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