# DE-R-015

> If both supplier and customer are located in Germany, the element "Buyer reference" (BT-10) shall be provided.

Checked against Peppol BIS Billing 3.0 2026.5

Canonical: https://einvoicecheck.eu/rules/de-r-015

## Official rule text

If both supplier and customer are located in Germany, the element "Buyer reference" (BT-10) shall be provided.