# BR-CL-03 Currency attribute must use ISO 4217 alpha-3

The currencyID attribute on amount elements must be a three-letter code from ISO 4217 alpha-3.

## Problem Description

The currencyID attribute on amount elements must be a three-letter code from ISO 4217 alpha-3.

> **ERROR**: XRechnung 3.0

## Context and Significance

This EN16931 core code-list rule guarantees that every monetary amount carries an unambiguous currency.

## Solution

Use a valid ISO 4217 alpha-3 code such as EUR, USD or CHF in every currencyID attribute.

- validate
- convert

## Valid Examples

- currencyID="EUR" on a line amount
- currencyID="USD" on a tax amount

## Invalid Examples

- currencyID="EURO" — four letters, not ISO 4217
- currencyID="€" — symbol instead of code

## Code Examples

### Valid XML
```
<cbc:LineExtensionAmount currencyID="EUR">100.00</cbc:LineExtensionAmount>
```

### Invalid XML
```
<cbc:LineExtensionAmount currencyID="EURO">100.00</cbc:LineExtensionAmount>
```

## Affected Fields

- [currencyID attribute on amount elements](/resources/xrechnung)

## Related Rules

- [BR-CL-04](/resources/kosit-validator-errors/br-cl-04-iso-4217-invoice-currency)
- [BR-CL-05](/resources/kosit-validator-errors/br-cl-05-iso-4217-tax-currency)

## Validation Tools

- [Official KoSIT Validator](https://erechnungsvalidator.service-bw.de/): Validate your XRechnung files against all BR-DE rules.
- [Convert PDF to XRechnung](/pdf-to-xrechnung): Automatic validation error fixes when converting.

## Related Resources

- [Official Specification](https://xeinkauf.de/xrechnung/)
- [Test Suite](https://github.com/itplr-kosit/xrechnung-testsuite)
- [Complete Error List](/resources/kosit-validator-errors): Overview of all German XRechnung validation rules.