# BR-55

> Each Preceding Invoice reference (BG-3) shall contain a Preceding Invoice reference (BT-25).

Checked against Peppol BIS Billing 3.0 2026.5

Canonical: https://einvoicecheck.eu/rules/br-55

## Official rule text

Each Preceding Invoice reference (BG-3) shall contain a Preceding Invoice reference (BT-25).

## Why did my invoice fail BR-55?

Each Preceding Invoice reference group (BG-3) must contain a Preceding Invoice reference (BT-25), the identifier of the earlier invoice being referenced (typically the original invoice that a corrective invoice or credit note relates to). Without it the reference to the prior invoice is empty and untraceable.

## Common causes

- cac:BillingReference/cac:InvoiceDocumentReference was added without its cbc:ID.
- The preceding invoice number was left blank on a corrective invoice or credit note.
- The issue date (BT-26) was populated but the mandatory reference ID was omitted.

## How do I fix it?

```
In cac:BillingReference/cac:InvoiceDocumentReference add <cbc:ID>INV-2026-0042</cbc:ID> (the preceding invoice number).
```