# IS-R-004

> If seller and buyer are icelandic then the invoice shall contain the buyers icelandic legal identifier — Ef seljandi og kaupandi eru íslenskir þá skal reikningurinn innihalda íslenska kennitölu kaupanda (BT-47).

Checked against Peppol BIS Billing 3.0 2026.5

Canonical: https://einvoicecheck.eu/rules/is-r-004

## Official rule text

If seller and buyer are icelandic then the invoice shall contain the buyers icelandic legal identifier — Ef seljandi og kaupandi eru íslenskir þá skal reikningurinn innihalda íslenska kennitölu kaupanda (BT-47).