Tip 1: First check what kind of error it is
Not every error calls for the same response. Distinguish between formal defects (missing tax number, incorrect date of supply), substantive errors (wrong quantity, wrong price), and errors in how tax is shown (wrong tax rate, tax shown without entitlement). Only the latter two categories affect the amount payable.
Tip 2: Know the mandatory information
| Mandatory information under section 14(4) UStG |
|---|
| Full name and address of both the supplier and the recipient |
| Tax number or VAT ID of the supplier |
| Date of issue |
| Consecutive, unique invoice number |
| Quantity and nature of the goods supplied or the scope of the service |
| Date of supply or of the service |
| Consideration broken down by tax rate, including any reductions |
| Tax rate and tax amount, or reference to a tax exemption |
For small-value invoices up to €250 gross, reduced information requirements apply. For reverse-charge supplies, the note "the recipient of the supply is liable for the tax" is mandatory.
Tip 3: Correct rather than rewrite
An invoice is corrected by issuing a document that refers clearly and specifically to the original invoice — citing its number and date — and corrects the erroneous item. You do not need to create an entirely new invoice. Important: the original invoice number remains in place; the correction document receives its own number.
Tip 4: Make use of the retroactive effect on input tax deduction
Under the case law of the European Court of Justice (ECJ) and the German Federal Fiscal Court (BFH), a correction of an invoice takes effect retroactively as of the date of the original issue, provided the original document contained the minimum information: the issuer of the invoice, the recipient of the supply, a description of the supply, the consideration, and the VAT separately stated. If any of these core items is missing, there is no retroactive effect — the input tax deduction then only becomes possible at the time of correction, together with interest on the back payment.
Tip 5: Document cancellations properly
If the invoice as a whole was addressed incorrectly, or if the service was never provided, cancel it in full: issue a cancellation invoice with a negative amount, referring to the original invoice, followed by a new invoice. Never delete an invoice that has already been sent from your system — this breaches the German principles of proper bookkeeping (GoBD) and jeopardises the propriety of your entire accounting.
Special case: VAT stated at too high a rate
Anyone who states VAT at too high a rate, or without entitlement, owes it to the tax office under section 14c UStG — even if it would not objectively have arisen. Correction is only possible if the risk to tax revenue has been eliminated, i.e. the recipient has not deducted the input tax, or has repaid it.
Communicating with the customer
- Name the error without playing it down.
- Enclose the corrected document and explain the change in one sentence.
- State a new payment deadline if the amount changes.
- Offer existing customers the option of destroying the old invoice or marking it as cancelled.
For larger amounts, or for business customers with formal invoice review processes, sending the correction by post remains standard practice — and provides the more robust evidence in the event of a dispute.