Which AI can create invoices? The honest answer

AI can draft; the business remains responsible

AI can draft invoices, but cannot guarantee compliance. A chat window alone does not ensure unique numbers, correct tax treatment or retention. That is not a statutory ban on AI: section 14 of the German VAT Act governs invoice details and format. The entire workflow matters, rather than the name of the writing tool.

Keep numbering, master data and records in invoicing software. Let AI draft descriptions and flag gaps. Integrated systems need the same checks. Purchased software must also fit the business and be configured correctly.

This article sorts out what you actually need, where AI genuinely helps, and what a wrong tax statement costs. For the opposite direction, incoming post, see our guide to AI in invoice checking.

Ten points to check on a standard invoice

First identify the invoice type. Section 14 (4) lists these details, some conditional. Section 33 UStDV covers small-value invoices; section 34a covers exempt small-business invoices. Missing details can endanger input tax recovery without necessarily losing it permanently. For standard invoices, check:

• Full name and address of you as well as the customer.
• Your tax number or your VAT identification number.
• Date of issue.
• A sequential number you issue exactly once.
• Quantity plus trade description of goods, or scope plus type of service.
• Date of supply, including when it matches the issue date; use the designated structured field in an e-invoice.
• Net amount by tax rate and exemption; agreed reductions not already reflected.
• Tax rate and tax amount, or a note pointing to an exemption.
• A note about the customer’s retention duty in the cases covered by section 14b (1), sentence 5.
• The word Gutschrift where the customer issues the document themselves.

The sequential number is the hard part

Invoice numbers need a reliable register. Section 14 (4) no. 4 requires a sequential number issued once; multiple numbering series are possible. Retrieve it from the system of record instead of generating one freely. Plausible is not a numbering system.

Changes must remain traceable. Section 146 (4) of the Fiscal Code prohibits changes that obscure original content or leave later additions unclear. Do not overwrite issued invoices. Keep originals and corrections separately, with a clear connection between them.

Retention is the third task. Section 14b (1) generally requires eight years, starting at the end of the year of issue. Check export, readability and retrieval in your archive. A saved chat does not replace that process.

Incorrectly stated VAT can be expensive

Incorrectly stated VAT can create an additional tax liability. Section 14c distinguishes different cases. The tax shown on an invoice is therefore not a harmless wording choice. Tax treatment and rates should come from approved records, rather than a model’s guess.

Consider a fictional business using the exemption under section 19. It issues 24 invoices to business customers for business use, each for EUR 800 plus 19 percent VAT. The checked calculation is 24 × 800 × 0.19 = EUR 3,648 of stated tax. This illustrates the size of an error, not a customer case or an automatic outcome for every recipient.

The BMF guidance on the small-business exemption places this tax statement under section 14c(1) from 2025. For supplies actually made to end consumers, the ministry describes an exception. Have corrections handled by a qualified tax professional: the recipient and transaction determine the treatment.

E-invoicing has deadlines and continuing exceptions

A plain PDF is not a structured e-invoice. Section 14 (1) requires machine-readable data; a hybrid ZUGFeRD document can combine a readable PDF with suitable XML data. The filename alone does not prove that the format is valid.

The finance ministry FAQ requires domestic businesses to be able to receive e-invoices from 2025; an email inbox is sufficient. For covered domestic B2B transactions, the general transition ends in 2026, or in 2027 with prior-year turnover of no more than EUR 800,000. Continuing exceptions include exempt small businesses, certain tax-exempt supplies and small-value invoices up to and including EUR 250. There is no blanket XML requirement from 2027.

The ministry identifies XRechnung and ZUGFeRD from version 2.0.1, excluding MINIMUM and BASIC-WL. KoSIT explains machine checks of format and business rules. Those checks do not establish that the invoiced work actually took place.

Three places where AI earns its keep

AI can help with wording and preliminary checks. Keep approved values and records in the invoicing system. Three useful tasks are:

• Work descriptions: turn timesheets into a checkable draft, such as “four hours maintaining system A in September” rather than “miscellaneous”. Quantities and work must match the records.
• Translation: the same description for overseas customers, with your own terminology supplied as a glossary.
• Preliminary review: let AI flag missing or inconsistent details. A responsible person checks the flags against the original; a clean AI report is not tax approval.

A prompt that checks instead of inventing

Start with a fictional invoice. Real data belongs only in an approved tool. This prompt collects evidence; check tax rates, numbers and results against records and fixed calculation rules afterward.

“Review this draft without changing it. Make a table for the details in section 14 (4): detail, quoted evidence, OPEN or FOUND. Check the supply date even if it equals the issue date. Mark conditional requirements separately. Use the simplified section 33 rules only when the total is at most EUR 250 and transactions under sections 3c, 6a and 13b are confirmed to be excluded. If invoice type, the small-business exemption or tax treatment is unclear, mark OPEN. Invent no numbers or details. List inconsistent figures for checking with fixed calculation rules. Do not approve sending.”

On handling customer data inside a prompt, see our article on redacting before an AI prompt; the free tool sits at prompt redaction.

An invoicing setup can start small

A free plan may cover low invoice volumes. sevdesk lists three invoices per month, including XRechnung and ZUGFeRD, in its free plan. Its Rechnung plan shows regular monthly rates of EUR 11.90 billed monthly or EUR 9.90 billed annually, both excluding VAT. Before promotional discounts, that is EUR 142.80 or EUR 118.80 net per year. Assuming 19 percent VAT, annual billing gives 118.80 × 1.19 = EUR 141.37 gross.

This is a pricing example, not protection against tax errors. With no more than three invoices each month, I would first check the free plan using a sample document. At higher volumes, exception handling, export and storage matter too. Paying for software does not remove the need to check tax treatment.

To get the stage before invoicing right, see our guide to writing quotes with AI. For rebuilding the whole document path, our process automation services lay out the approach.

Questions that keep coming up

Choosing a tool does not replace checking it. These answers separate wording, format and retention:

• May ChatGPT write an invoice? It can prepare a draft. Correct details, a permitted format and proper handling of the record are what matter. Check these outside free-form text generation.
• Is a Word template enough? It can be a starting point where an ordinary invoice is permitted. Small-value invoices follow section 33, including its exclusions; an invoice number is not one of its four minimum details. Retention is still required.
• Can AI produce an XRechnung? XML can be generated. A validator checks technical rules; accurate content and actual supplies still need checking. Invoicing products do not all provide the same checks.

What to do this week

Take a sample invoice and first identify its type. Check the applicable details, numbering workflow and storage. Where an e-invoice is required, add a test export and format validation.

If something is missing, fix the template first and the workflow second. If you are unsure which of the three duties is shaky in your own house, request an initial consultation.