What it means
When the seller is Italian, the seller's postal address must contain the city (BT-37). EN 16931 makes it optional; the Italian rules do not.
Why it matters
The Italian rules require the seller's postal address on the invoice. Without the city the invoice fails the check and is rejected.
How to fix it
Open your company details in your invoicing software, go to the address and fill in the city or town. In the XML this is cbc:CityName in cac:PostalAddress of cac:AccountingSupplierParty.
The rule as published
Read the rule on the publisher's site
Business terms: BT-37
Where this rule applies
| Rule set | Version |
|---|---|
| Peppol BIS Billing 3.0 (invoice) | 2026.5 |
| Peppol BIS Billing 3.0 (credit note) | 2026.5 |
Check your file
Drop your e-invoice to see whether IT-R-003 still fails, and which other rules do.