# BR-27

> The Item net price (BT-146) must not be negative. Check cac:InvoiceLine/cac:Price/cbc:PriceAmount.

Checked against Peppol BIS Billing 3.0 2026.5

Canonical: https://einvoicecheck.eu/rules/br-27

## Official rule text

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

## Why did my invoice fail BR-27?

The Item net price (BT-146) is the price of a single item after subtracting any item price discount, and it must be zero or positive. A negative net price is not permitted because line-level allowances/charges and discounts are modelled separately, not as a negative price.

## Common causes

- A credit or refund line was modelled by negating the unit price instead of using a credit note or an allowance
- A discount was applied by making cbc:PriceAmount negative rather than using cac:AllowanceCharge on the price
- Data-mapping error where a signed amount from an ERP was passed through unchanged

## How do I fix it?

```
Set a non-negative price and model reductions separately: <cac:Price><cbc:PriceAmount currencyID="EUR">100.00</cbc:PriceAmount></cac:Price>. To reduce it, use cac:AllowanceCharge (ChargeIndicator=false) on the price rather than a negative PriceAmount.
```