Writing an invoice: the mandatory details under section 14 UStG

The mandatory details

• full name and address of the supplier and of the recipient
• tax number or VAT ID of the issuer
• date of issue
• a consecutive invoice number that is unique
• quantity and customary description of the goods, or type and extent of the service
• date or period of the supply or service
• the amount, split by tax rates and exemptions, including agreed reductions such as discounts
• the applicable tax rate and the tax amount, or a note on the exemption
• for credit notes the word "credit note"
• for reverse-charge supplies a note that the recipient is liable for the tax

Small-amount invoices up to 250 euros

For invoices up to 250 euros gross fewer details are enough: name and address of the issuer, date of issue, quantity and type of the service, the amount including tax in one sum and the tax rate or a note on the exemption. Recipient name and address and the invoice number are not required then.

The invoice number

The number has to be consecutive and unique. You may keep several number ranges, for example for invoices and credit notes, or include the year in the number. You must be able to explain gaps, for example by a cancelled invoice. You do not change finalized invoices, you correct them with a cancellation invoice or credit note.

Common mistakes

• date of supply missing or different from the invoice date without explanation
• recipient name imprecise, for example without the legal form
• several tax rates but only one total
• tax number missing or not yours
• invoice number assigned twice

How Saldiqo helps

Saldiqo checks all mandatory details for your country and legal form before finalizing, assigns numbers consecutively and locks finalized invoices against changes. The note for small businesses, reverse charge or intra-community supplies is added automatically.

Frequently asked questions

Does every invoice need a tax number?

Yes, the issuer's tax number or VAT ID.

May the invoice number contain letters?

Yes, for example "INV-2026-0042". What matters is that it is unique and consecutive.

How do I correct an invoice?

With a cancellation invoice or credit note and a new invoice. The original stays unchanged.

When is a small-amount invoice enough?

For a gross amount up to 250 euros.

What is a period of supply?

The period in which you performed the service, for example "1 to 31 October 2026".

More guides

• E-invoicing in Germany: obligation, formats and deadlines
• The EÜR (cash-basis profit calculation) explained simply
• GoBD for self-employed people: the essentials
• Invoicing as a small business: how to do it right
• Writing a payment reminder: deadlines, interest and fees
• Assigning invoice numbers correctly
• XRechnung or ZUGFeRD: what is the difference?