# BT-133 Invoice line buyer accounting reference

A textual value that specifies where to book the relevant data into the buyer's financial accounts.

## Quick answer

A textual value that specifies where to book the relevant data into the buyer's financial accounts.

> **Line items**: The goods or services on each invoice line, including quantities, prices, and VAT.

## In plain language

A textual value that specifies where to book the relevant data into the buyer's financial accounts.

A textual value that specifies where to book the relevant data into the buyer's financial accounts.

Used for cost center allocation and internal accounting purposes.

## What you usually enter here

Free text accounting reference

Typical valid values include: CC123, DEPT-456, PROJECT-X

Optional according to EN 16931-1.

## What goes wrong often

Avoid values like: , AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

Relevant rule codes: BR-2

## Examples in context

Used for cost center allocation and internal accounting purposes.

Optional according to EN 16931-1.

## Valid Examples

- CC123
- DEPT-456
- PROJECT-X

## Invalid Examples

- AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

## Related Fields

Used for cost center allocation and internal accounting purposes.

- [BT-126 Invoice line identifier](/resources/xrechnung/bt-126-invoice-line-identifier)

## 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-133

### Data Type:
text

### Cardinality:
0..1

### Requirement:
Optional

### Max Length:
50 characters

### Since Version:
Optional

## XML Implementation

### UBL 2.1 Syntax
```
/Invoice/cac:InvoiceLine/cac:AccountingCost/cbc:ID
```

### CII (UN/CEFACT) Syntax
```
/CrossIndustryInvoice/SupplyChainTradeTransaction/ApplicableHeaderTradeSettlement/ram:SpecifiedTradeSettlementLineMonetarySummation/ram:AccountingAccount/ram:ID
```

## Validation Rules

### BR-2
BR-2

## Why the standard cares about this field

### Business Context
Used for cost center allocation and internal accounting purposes.

### Legal Requirement
Optional according to EN 16931-1.

## 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)