Invoice Mandatory Fields Checker §14 UStG
Interactively verify that your invoice contains all legally required fields — and protect your input VAT (Vorsteuer) deduction rights.
Mandatory fields under §14(4) UStG (full invoice)
What mandatory fields must a German invoice contain under §14 UStG?
Section 14(4) of the German Umsatzsteuergesetz (UStG) specifies precisely which details an invoice must contain for the recipient to claim input VAT (Vorsteuer). If even one mandatory item is missing, the tax authority may refuse the entire input VAT deduction — even if the underlying supply was genuinely made.
For invoices with a gross total of up to €250, there is a simplification: the Kleinbetragsrechnung (simplified invoice) under §33 of the Umsatzsteuerdurchführungsverordnung (UStDV) requires fewer mandatory fields. In particular, the recipient's name/address and the issuer's tax number are not strictly required.
This interactive checker helps you verify invoice completeness. Tick the fields that are present on your invoice, or upload an XRechnung/ZUGFeRD XML file so the checker can detect fields automatically. The result shows which fields are missing and why they matter for the VAT deduction.
Correct invoicing has become especially important since the introduction of mandatory e-invoicing in 2025. Electronic invoices in XRechnung or ZUGFeRD format must contain all mandatory fields in structured, machine-readable form. Missing mandatory fields cause validation failure and rejection by public-sector buyers.
Our tool checks both full invoices under §14(4) UStG and simplified invoices under §33 UStDV. For XML mode, the built-in XRechnung parser automatically identifies key structured fields.
How to use this checker
- Select invoice type — Choose whether you are checking a full invoice (gross total above €250) or a simplified invoice (≤ €250 gross). Mandatory fields differ between the two types.
- Tick present fields (checklist mode) — Go through each mandatory field and tick it if it is present and correct on your invoice. Each item shows why the field matters.
- Or upload XML — Switch to the "XRechnung/ZUGFeRD XML" tab, paste or upload the XML file, and the checker auto-detects which fields are present.
- Run the check — Click "Check mandatory fields". You get an immediate overview of present and missing fields, plus a completeness score.
- Export result (Pro) — Pro users can export the full check report — useful as accounting documentation or as a basis for issuing a corrected invoice.
This checker does not replace legal or tax advice. For disputed invoices, consult a qualified tax advisor (Steuerberater).
How the checker works
In checklist mode, the checker compares your ticks against the statutory catalogue of mandatory fields — either §14(4) UStG (full invoice) or §33 UStDV (simplified invoice). All evaluation is done locally in your browser.
In XML mode, the uploaded XRechnung or ZUGFeRD file is parsed using the built-in parser. Detected fields (invoice number, date, name/address, tax number, amounts, tax codes) are automatically marked as present. Fields not found in the XML are flagged as missing.
The completeness score is the percentage of mandatory fields present out of the total required for the selected invoice type.
Use cases
Invoice issuers
Check your outgoing invoices before sending to ensure all mandatory fields are included — avoiding returns and corrected invoice hassle.
Accounting & invoice approval
Verify incoming supplier invoices for completeness before claiming input VAT.
XRechnung validation
Upload your XRechnung or ZUGFeRD XML and verify that all mandatory fields are present in structured form.
Training & compliance
Use the checklist as a training aid for new staff in the invoicing or accounts-payable department.
Example check
A marketing agency checks an incoming invoice for €850 net. The invoice includes name/address of both parties, invoice date and number, service description, and gross amount. Missing: the date of supply and a separate VAT breakdown.
Fields checked: ✓ Issuer name/address ✓ Recipient name/address ✓ Invoice date ✓ Invoice number ✓ Service description ✗ Date of supply → MISSING (input VAT at risk) ✗ Net amount / VAT rate / VAT amount → MISSING Score: 5/8 = 62.5% — corrected invoice required
Without the date of supply and a separate VAT breakdown, the recipient's input VAT deduction is at risk.
Tips & limitations
Tipps
- The date of supply must always be stated — even when it matches the invoice date. A note like "Date of supply: same as invoice date" is sufficient.
- When multiple VAT rates apply (e.g. 19% and 7%), each net amount, rate, and VAT amount must be shown separately.
- Digital invoices (PDF, email) have exactly the same mandatory fields as paper invoices — the delivery channel makes no difference.
- Note: additional or different requirements apply to certain supplies (travel expenses, construction services, reverse charge, etc.).
Einschränkungen
- XML mode only detects fields present in standard UBL and CII elements. Free-text fields or non-standard namespace structures may not be recognised.
- This checker verifies field presence, not content accuracy (e.g. correct VAT amount calculation).
- Sector-specific rules (construction services, intra-EU supplies, reverse charge) are not fully covered.
- Invoices exempt under §4 UStG or reverse-charge cases have specific requirements not fully represented in this checker.
Frequently asked questions
What mandatory fields must a German invoice contain under §14 UStG?
A full invoice must contain: name and address of issuer and recipient, the issuer's tax number or VAT ID, issue date, sequential invoice number, quantity/type of goods or services, date of supply, net amount broken down by VAT rate, the applicable VAT rate and amount (or exemption note), and the total gross amount.
What is a Kleinbetragsrechnung and what fields does it require?
A Kleinbetragsrechnung (simplified invoice) under §33 UStDV is an invoice with a gross total of up to €250. It only requires: issuer name/address, issue date, description of goods/services, gross amount, and VAT rate or exemption note. The recipient's name/address and an invoice number are not required.
What happens if a mandatory field is missing?
The tax authority may fully deny the recipient's input VAT deduction. In some cases a retrospective correction is possible (Rechnungsberichtigung), but this involves effort and risks.
Can a defective invoice be corrected retroactively?
Yes, under certain conditions a correction under §31(5) UStDV is possible. However, the correction takes effect from the date of correction — not retroactively from the original invoice date. This can have adverse tax consequences.
Must the date of supply be stated if it matches the invoice date?
Yes. The date of supply must always be stated. If it is identical to the issue date, a note such as "Date of supply equals invoice date" is sufficient.
What applies when an invoice contains multiple VAT rates?
When mixed VAT rates apply (e.g. 19% and 7%), the net amount, VAT rate, and VAT amount must be stated separately for each rate. A single combined figure is not sufficient.
What is the difference between a Steuernummer and a USt-IdNr.?
The Steuernummer (tax number) is assigned by the local tax office and typically begins with a three-digit office code. The USt-IdNr. (VAT ID) starts with "DE" and is used for cross-border EU transactions. Either number suffices on a domestic invoice.
Must XRechnung files also contain all mandatory fields?
Yes. XRechnung and ZUGFeRD files must contain all mandatory §14 UStG fields in structured, machine-readable form, as specified by the EU Core Invoice Usage Specification (EN 16931). Missing mandatory fields cause validation rejection.
Is a sequential invoice number required on simplified invoices?
No. For Kleinbetragsrechnungen (≤ €250 gross) under §33 UStDV, a sequential invoice number is not required. For full invoices, it is mandatory and must be unique and sequential.