# BR-DEC-05: Write the document charge amount with no more than two decimals

A document-level charge has a `cbc:Amount` with more than two digits after the decimal point. Write the charge, such as a freight fee, to two decimals.

- Layer: EN 16931
- Severity: fatal (the document is invalid)
- Topics: Allowances and charges
- Official definition: https://docs.peppol.eu/poacc/billing/3.0/rules/ubl-tc434/BR-DEC-05/
- Explanation last updated: 2026-09-28

## The short answer

`BR-DEC-05` fails when the `cbc:Amount` of a charge on the whole document, a root-level `cac:AllowanceCharge` whose `cbc:ChargeIndicator` is `true`, has more than two characters after the decimal point. Round the charge to two decimals and write `3.50` rather than `3.500`.

In the recorded invoice the charge is 10 percent of 35.00, correctly 3.50, and fails only because of the third digit. `UBL-DT-01` reports the same `cbc:Amount`.

## What the rule checks

The rule selects every `cac:AllowanceCharge` that is a direct child of the root and has `cbc:ChargeIndicator` set to `true`, and counts what follows the decimal point in its `cbc:Amount`. More than two characters fail, whatever they are.

A small unrounded remainder is caught here even when the arithmetic rules let it through. When tried, a charge of `3.504` reported only this rule and `UBL-DT-01`: `BR-CO-12` rounds the sum of the charges to 3.50 before comparing it with the charge total, and `PEPPOL-EN16931-R040` allows 0.02 against 10 percent of 35.00. At `3.506` the sum rounds to 3.51, and `BR-CO-12` was reported as well.

The base amount of the same charge is counted by `BR-DEC-06`, and the amount of a document allowance by `BR-DEC-01`: the value of `cbc:ChargeIndicator` decides which rule reads the element.

| Term | Meaning | UBL element |
|---|---|---|
| BT-99 | Document level charge amount | `cac:AllowanceCharge[cbc:ChargeIndicator = true]/cbc:Amount` |

## How an integration ends up here

Possible causes, from the shape of the rule rather than from measured usage:

- A percentage charge is calculated as base times rate and the product is written without rounding.
- Freight or handling fees are held in a price table with three decimals and copied into the charge as stored.
- The charge and the unit prices go through one formatter, configured for the precision of the prices.

## How to fix it

1. Calculate the charge, round it to two decimals, and write that figure to `cbc:Amount` in the document-level `cac:AllowanceCharge` with `cbc:ChargeIndicator` of `true`.
2. Build `cbc:ChargeTotalAmount` from the rounded charges, so that `BR-CO-12` compares like with like.
3. Add the rounded charge to the taxable amount of its VAT category, so that the VAT breakdown agrees with it.
4. Format the base amount of a percentage charge the same way; `BR-DEC-06` applies to it separately.

## Before and after

These are fragments, not complete documents. The complete synthetic documents they come from are linked below.

Fragment of the failing invoice: a 10 percent charge on 35.00 written as 3.500

```xml
<cac:AllowanceCharge>
  <cbc:ChargeIndicator>true</cbc:ChargeIndicator>
  <cbc:AllowanceChargeReasonCode>CG</cbc:AllowanceChargeReasonCode>
  <cbc:AllowanceChargeReason>Example document charge</cbc:AllowanceChargeReason>
  <cbc:MultiplierFactorNumeric>10</cbc:MultiplierFactorNumeric>
  <cbc:Amount currencyID="GBP">3.500</cbc:Amount>
  <cbc:BaseAmount currencyID="GBP">35.00</cbc:BaseAmount>
  <!-- tax category omitted from this fragment -->
</cac:AllowanceCharge>
```

Fragment of the corrected invoice: the same charge written as 3.50

```xml
<cac:AllowanceCharge>
  <cbc:ChargeIndicator>true</cbc:ChargeIndicator>
  <cbc:AllowanceChargeReasonCode>CG</cbc:AllowanceChargeReasonCode>
  <cbc:AllowanceChargeReason>Example document charge</cbc:AllowanceChargeReason>
  <cbc:MultiplierFactorNumeric>10</cbc:MultiplierFactorNumeric>
  <cbc:Amount currencyID="GBP">3.50</cbc:Amount>
  <cbc:BaseAmount currencyID="GBP">35.00</cbc:BaseAmount>
  <!-- tax category omitted from this fragment -->
</cac:AllowanceCharge>
```

The document charge is `3.500` in the failing invoice and `3.50` in the corrected one; its percentage, base amount and tax category are the same, and the charge total of 3.50 fits both. The failing document reports `BR-DEC-05` at the second `cac:AllowanceCharge`, which is the charge, and `UBL-DT-01` at the `cbc:Amount` inside it. `UBL-DT-01` holds every amount element to two decimals except the item net price and the amounts of a price-level allowance, and a document charge is not among those exceptions, so the two findings arrive together and one correction clears both.

### What the validator reported

- The failing invoice reports **BR-DEC-05** and [UBL-DT-01](https://ironfang.com/docs/finance/rules/UBL-DT-01.md). The corrected document passes every layer with no findings.
  - [Download the failing XML](https://ironfang.com/finance/rule-examples/BR-DEC-05-invalid.xml)
  - [Download the corrected XML](https://ironfang.com/finance/rule-examples/invoice-rich.xml)

Recorded on phive 12.1.0 / phive-rules-peppol 4.5.6 / Saxon-HE 12.10, the engine behind the free validator, using synthetic data. A recorded result is regression evidence for these documents; it is not a certification.

## Where it applies

- Applies to UBL `Invoice` and `CreditNote`. When tried, a credit note with a document charge of `3.500` reported the same pair.
- Only charges on the document are in scope. A charge on a line is counted by `BR-DEC-27`, and Peppol does not allow a charge inside `cac:Price` at all (`PEPPOL-EN16931-R044`).
- The currency does not change the limit: `currencyID` plays no part in the count.

## Related rules

- [UBL-DT-01 is reported for the same charge amount, as the general two-decimal limit on amounts](https://ironfang.com/docs/finance/rules/UBL-DT-01.md)
- [BR-CO-12 checks that the charge total equals the rounded sum of the document charges](https://ironfang.com/docs/finance/rules/BR-CO-12.md)
- [BR-DEC-06 applies the same limit to the base amount of a document charge](https://ironfang.com/docs/finance/rules/BR-DEC-06.md)
- [BR-DEC-11 applies the same limit to the charge total in the monetary totals](https://ironfang.com/docs/finance/rules/BR-DEC-11.md)

## Scope and source

Written for Peppol BIS Billing 3.0.21 (May 2026), EN 16931 1.3.16, as applied to UBL 2.1 Invoice and CreditNote documents. Other profiles, syntaxes and releases can define this identifier differently. Guidance version 2026-09-28.1: source checked 2026-09-28, explanation last updated 2026-09-28.

[The official definition of BR-DEC-05](https://docs.peppol.eu/poacc/billing/3.0/rules/ubl-tc434/BR-DEC-05/) carries the normative wording and test. This page is our explanation of it, not a copy.

Guidance does not change the engine verdict. Fixing this finding does not mean the document passes every layer, and validation does not certify legal or tax compliance or transmit a document over Peppol.

## Links

- [This rule as a web page](https://ironfang.com/docs/finance/rules/BR-DEC-05)
- [Free Peppol invoice validator](https://ironfang.com/tools/peppol-validator)
- [Rule index](https://ironfang.com/docs/finance/rules.md)
- [Ironfang Finance API docs](https://ironfang.com/docs/finance)
- The same rule is available to MCP clients as the tool `finance.rule.get` on https://mcp.ironfang.com/mcp