# BT-121 VAT Exemption Reason Code

A coded reason for a VAT exemption or special VAT treatment, using the allowed VAT exemption reason code list.

## Quick answer

A coded reason for a VAT exemption or special VAT treatment, using the allowed VAT exemption reason code list.

> **Taxes and totals**: VAT treatment, tax breakdowns, and document totals that validators check closely.

- validate
- convert

## In plain language

A coded reason for a VAT exemption or special VAT treatment, using the allowed VAT exemption reason code list.

A coded reason for a VAT exemption or special VAT treatment, using the allowed VAT exemption reason code list.

Lets receiving systems process exempt and special VAT treatments without relying only on free text.

## What you usually enter here

Code from the VAT exemption reason code list

Typical valid values include: VATEX-EU-AE, VATEX-EU-IC, VATEX-EU-O

When present, the code must use the EN 16931 allowed VAT exemption reason code list.

## What goes wrong often

Avoid values like: AE, REVERSE_CHARGE, 0

Relevant rule codes: BR-AE-10, BR-E-10, BR-G-10, BR-IC-10, BR-O-10, BR-S-10, BR-Z-10, BR-CL-22

## Examples in context

Lets receiving systems process exempt and special VAT treatments without relying only on free text.

When present, the code must use the EN 16931 allowed VAT exemption reason code list.

## Valid Examples

- VATEX-EU-AE
- VATEX-EU-IC
- VATEX-EU-O

## Invalid Examples

- AE
- REVERSE_CHARGE
- 0

## Related Fields

Lets receiving systems process exempt and special VAT treatments without relying only on free text.

- [BT-118 VAT Category Code](/resources/xrechnung/bt-118-vat-category-code)
- [BT-119 VAT Category Rate](/resources/xrechnung/bt-119-vat-category-rate)
- [BT-120 VAT Exemption Reason Text](/resources/xrechnung/bt-120-vat-exemption-reason-text)

## XML mapping and field facts

Open the technical reference if you need XML paths, validator rule codes, legal wording, or schema-specific mapping details.

### Field ID:
BT-121

### Data Type:
code

### Cardinality:
0..1

### Requirement:
Optional

### Since Version:
Conditional when a coded VAT exemption reason is provided

## XML Implementation

### UBL 2.1 Syntax
```
/Invoice/cac:TaxTotal/cac:TaxSubtotal/cac:TaxCategory/cbc:TaxExemptionReasonCode
```

### CII (UN/CEFACT) Syntax
```
/CrossIndustryInvoice/SupplyChainTradeTransaction/ApplicableHeaderTradeSettlement/ram:ApplicableTradeTax/ram:ExemptionReasonCode
```

## Validation Rules

### BR-AE-10
BR-AE-10

### BR-E-10
BR-E-10

### BR-G-10
BR-G-10

### BR-IC-10
BR-IC-10

### BR-O-10
BR-O-10

### BR-S-10
BR-S-10

### BR-Z-10
BR-Z-10

### BR-CL-22
BR-CL-22

## Why the standard cares about this field

### Business Context
Lets receiving systems process exempt and special VAT treatments without relying only on free text.

### Legal Requirement
When present, the code must use the EN 16931 allowed VAT exemption reason code list.

## Official sources and tools

- [KoSIT Validator](https://erechnungsvalidator.service-bw.de/)
- [Invoice Converter](/pdf-to-xrechnung)
- [XRechnung Standard](https://xeinkauf.de/xrechnung/)
- [Test Suite](https://github.com/itplr-kosit/xrechnung-testsuite)