# BT-87 Payment card primary account number

Masked primary account number of the payment card when card payment details are referenced.

## Quick answer

> **Delivery and payment**: Delivery dates, payment means, and the operational context around settlement.

- [Validate XML](/en/xrechnung-validator?source=resource&bt=BT-87)
- [Convert invoice](/en/pdf-to-xrechnung?source=resource&bt=BT-87)

## In plain language

Only use this in rare card-payment scenarios and never expose the full card number.

## What you usually enter here

Masked card number only

Typical valid values include: 123456******1234

Optional according to EN 16931-1, but BR-51 forbids exposing the full card number. Only masked values are acceptable.

## Where the field sits

BT-87 belongs to the Payment part of the invoice. UBL 2.1 Syntax: Invoice › cac:PaymentMeans › cac:CardAccount › cbc:PrimaryAccountNumberID. CII (UN/CEFACT) Syntax: rsm:CrossIndustryInvoice › rsm:SupplyChainTradeTransaction › ram:ApplicableHeaderTradeSettlement › ram:SpecifiedTradeSettlementPaymentMeans › ram:ApplicableTradeSettlementFinancialCard › ram:ID.

## What goes wrong often

Avoid values like: 4111111111111111

Relevant rule codes: BR-51

## Valid Examples

- 123456******1234

## Invalid Examples

- 4111111111111111

## Related Fields

- [BT-88 Payment card holder name](/resources/xrechnung/bt-88-payment-card-holder-name)
- [BT-81 Payment means type code](/resources/xrechnung/bt-81-payment-means-type-code)

## 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-87

### Data Type:
text

### Cardinality:
0..1

### Requirement:
Optional

### Max Length:
35 characters

## XML Implementation

### UBL 2.1 Syntax
```
/Invoice/cac:PaymentMeans/cac:CardAccount/cbc:PrimaryAccountNumberID
```

### CII (UN/CEFACT) Syntax
```
/rsm:CrossIndustryInvoice/rsm:SupplyChainTradeTransaction/ram:ApplicableHeaderTradeSettlement/ram:SpecifiedTradeSettlementPaymentMeans/ram:ApplicableTradeSettlementFinancialCard/ram:ID
```

## Validation Rules

### BR-51
BR-51

## Check whether your XRechnung sets BT-87 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-51. 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.

## 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)