# PEPPOL-EN16931-R042

> Allowance/charge percentage MUST be provided when allowance/charge base amount is provided.

Checked against Peppol BIS Billing 3.0 2026.5

Canonical: https://einvoicecheck.eu/rules/peppol-en16931-r042

## Official rule text

Allowance/charge percentage MUST be provided when allowance/charge base amount is provided.

## Why did my invoice fail PEPPOL-EN16931-R042?

If an allowance or charge base amount (BT-93/BT-100) is supplied, its percentage (BT-94/BT-101) must also be supplied. Base and percentage form a pair; a base without a rate is incomplete and cannot be validated against the amount.

## Common causes

- BaseAmount is present but MultiplierFactorNumeric (percentage) was omitted.
- The percentage field was left null in the source data.
- Only the base and the resulting amount were mapped, skipping the percentage.

## How do I fix it?

```
Add the missing percentage alongside the base: <cbc:BaseAmount currencyID="EUR">100.00</cbc:BaseAmount><cbc:MultiplierFactorNumeric>10</cbc:MultiplierFactorNumeric>
```