Definition
An invoice, also called “invoicing”, is a financial document. It is a request from a company to its customer to pay the agreed remuneration for a service rendered.
Contents of an Invoice
An invoice bills delivered goods or services. The basis for this is, for example, an order or a purchase contract. According to §14 UStG, the following items must be listed in an invoice:
- Name & address of the supplying company,
- Tax number & VAT ID of the supplying company,
- Name & address of the customer,
- VAT ID of the customer (only if the service was provided tax-free within the EU),
- Date of the invoice,
- Date of delivery/service,
- Unique, sequential invoice number,
- Description of the delivery / service & quantity,
- Invoice amount (subdivided into net amount, tax rate & amount, gross amount).
Not legally required, but relevant, would also be details such as:
- Customer number,
- Payment deadline,
- Bank account details (e.g. also as a QR Code),
- Contact details.
Sending & Retaining Invoices
Invoices can be transmitted in paper form or electronically as an e-invoice.
In addition to digital archiving, e.g. with a digital document entry system or simply in a file management system, you must, based on legal requirements that changed on 01.01.2025, retain them for 8 years in paper format or, in the case of e-invoices, in digital form. The retention obligation always begins and ends on 31 December of a year.
QR Codes and ZUGFeRD
With the help of QR Codes (GiroCode or SwissQR Code) on the invoice, payment can be made easier for customers. The invoice is created with a QR Code that summarises all payment information. This allows customers to transfer the payment quickly and without errors directly after scanning the code.
ZUGFeRD invoices are a format of e-invoices that format these when created so that systems can automatically read these PDF formats and thus digitise them immediately.