# BT-125 Attached Document

The binary content of a supporting document embedded directly in the invoice.

## Quick answer

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

- [Validate XML](/en/xrechnung-validator?source=resource&bt=BT-125)
- [Convert invoice](/en/pdf-to-xrechnung?source=resource&bt=BT-125)

## In plain language

The binary content of a supporting document embedded directly in the invoice.

The binary content of a supporting document embedded directly in the invoice.

Embeds evidence directly in the invoice package when the receiver needs the document with the invoice.

## What you usually enter here

Base64 encoded binary object with a valid MIME code and unique filename

Typical valid values include: Base64-encoded PDF attachment

Embedded supporting documents must use allowed MIME codes, and XRechnung requires attachment filenames to be unique.

## What goes wrong often

Avoid values like: Raw file path, Plain text without binary encoding

Relevant rule codes: BR-CL-24, BR-DE-22

## Examples in context

Embeds evidence directly in the invoice package when the receiver needs the document with the invoice.

Embedded supporting documents must use allowed MIME codes, and XRechnung requires attachment filenames to be unique.

## Valid Examples

- Base64-encoded PDF attachment

## Invalid Examples

- Raw file path
- Plain text without binary encoding

## Related Fields

Embeds evidence directly in the invoice package when the receiver needs the document with the invoice.

- [BT-122 Supporting Document Reference](/resources/xrechnung/bt-122-supporting-document-reference)
- [BT-123 Supporting Document Description](/resources/xrechnung/bt-123-supporting-document-description)
- [BT-124 External Document Location](/resources/xrechnung/bt-124-external-document-location)

## 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-125

### Data Type:
binary

### Cardinality:
0..1

### Requirement:
Optional

### Since Version:
Optional when the supporting document is embedded in the invoice

## XML Implementation

### UBL 2.1 Syntax
```
/Invoice/cac:AdditionalDocumentReference/cac:Attachment/cbc:EmbeddedDocumentBinaryObject
```

### CII (UN/CEFACT) Syntax
```
/CrossIndustryInvoice/SupplyChainTradeTransaction/ApplicableHeaderTradeAgreement/ram:AdditionalReferencedDocument/ram:AttachmentBinaryObject
```

## Validation Rules

### BR-CL-24
BR-CL-24

### BR-DE-22
BR-DE-22

## Check whether your XRechnung sets BT-125 correctly

Upload the XML file to the free validator. It applies the KoSIT rules for XRechnung 3.0 and names each finding with its rule ID, for this field for example BR-DE-22, BR-CL-24. Creating a new invoice instead? The converter checks the invoice against the same rules and shows the findings before download.

- [Validate XML](/en/xrechnung-validator)
- [Convert invoice](/en/pdf-to-xrechnung)

Free, no account needed. XML file up to 2 MB.

## Why the standard cares about this field

### Business Context
Embeds evidence directly in the invoice package when the receiver needs the document with the invoice.

### Legal Requirement
Embedded supporting documents must use allowed MIME codes, and XRechnung requires attachment filenames to be unique.

## Official sources and tools

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