Writing the final invoice: What self-employed people need to consider

What is a final invoice – and when do you need it?

You always issue a final invoice when a project or service has been fully completed – for example after a construction contract, a comprehensive service or a long-term project. It summarizes all previous services and payments already received and shows the total amount still outstanding.

Important to know: German tax law does not refer to the “final invoice”, but to the final invoice (Section 14 (5) UStG). However, both terms mean the same thing.

When is a final invoice necessary?

You usually need a final invoice if:

• you have previously issued partial invoices or down payment invoices

• you have completed a project with agreed partial payments

• you invoice a VOB-compliant construction service

The final invoice takes into account all partial invoices that have already been issued – it therefore represents the financial conclusion of the entire project.

Mandatory information in a final invoice

The final invoice must contain all mandatory components of a regular invoice:

• Full name and address of you and your customer

• Tax number or VAT ID

• Consecutive invoice number and invoice date

• Service date or service period

• Description of the service provided

• Net amount, sales tax and gross amount

A final invoice must also be included:

• An overview of all partial payments already received (with amount and VAT)

• The outstanding balance still to be paid

• The corresponding sales tax on the remaining amount

Tip: Ensure transparency and traceability so that your invoice is clear and verifiable for both customers and the tax office.

Special features of construction services (VOB)

If you invoice construction services in accordance with VOB, special requirements apply:

• All services rendered must be listed cumulatively

• Previous partial invoices must be listed and offset correctly

• The VAT portion of the advance payments already paid must also be shown separately

The advantage: you and your customer can see at any time how much has already been paid – and what is still outstanding.

Paper, PDF or X-bill?

You can send the final invoice in paper form, as a PDF or as an electronic invoice.
⚠️ Attention in the B2B sector: E-invoices have been mandatory for business customers since 2025. Public clients are already required to use the X-invoice – a structured, machine-readable format.

Conclusion

The final invoice is the last step in the billing of a project – and is particularly important if you have previously issued partial or partial invoices. Make sure that all payments and mandatory details are clearly presented so that your customer can pay the remaining amount correctly and you can settle your accounts correctly for tax purposes.

Would you like to know how to invoice correctly before the project starts? Then read our article on advance payment invoicing for the self-employed.