How to Find or Get a Leitweg-ID for Invoicing German Authorities

Suppliers find the Leitweg-ID in the purchase order or contract from the German public authority, which provides it when it places the order. If it is missing, ask the authority's invoice office. Only public bodies can apply for a Leitweg-ID: at federal level through the central finance service (ZFB), in the states through the office each state designates.

Last reviewed: September 2026

Do you need a Leitweg-ID at all?

A Leitweg-ID is the electronic address of a public-sector invoice recipient in Germany. Its structure, check digit and examples are explained in what is a Leitweg-ID?. How you get the right one depends on which side of the invoice you are on:

Businesses do not need a Leitweg-ID of their own, not even for German B2B e-invoicing, which has applied since 1 January 2025. The federal e-invoicing FAQ (opens in a new tab) states this explicitly.

How suppliers find the right Leitweg-ID

The following steps lead to the right ID in most cases. Always start with the documents for the specific order.

1. Check the purchase order and contract

According to the federal FAQ, the Leitweg-ID is communicated when the order is placed. Search the purchase order, order letter, framework agreement or award letter for these terms:

• Leitweg-ID or Leitweg-Identifikationsnummer
• Käuferreferenz or buyer reference
• BT-10
• instructions for electronic invoicing (elektronische Rechnungsstellung)

Leitweg-IDs of federal authorities start with 991, 992 or 993. Those of state and municipal authorities start with the two-digit state code, for example 05 for North Rhine-Westphalia or 09 for Bavaria. They always end with a hyphen and two digits.

Take the purchase order number (BT-13) and, if given, your supplier number (BT-29) from the same order. On invoices to federal authorities both are mandatory under § 5 of the E-Invoicing Ordinance (E-RechV) (opens in a new tab) whenever they were provided with the order.

2. Read the authority's invoicing instructions

Some authorities publish instructions for suppliers, often in a procurement section or on a page for suppliers (Für Lieferanten). These may list which Leitweg-ID applies to which unit and which submission channel is expected. Use such information only if it clearly matches your order.

3. Ask the invoice office

If the ID is missing, ask for it specifically, preferably in writing, either your contact person or the invoice office (Rechnungseingang or Kreditorenbuchhaltung, the accounts payable team). Quote the order, its date and the order number. A short request is enough, for example:

For the electronic invoice relating to your purchase order no. 4711 of 1 September 2026, we need the Leitweg-ID (buyer reference, BT-10) of the responsible invoice recipient. Please also let us know which channel we should use to submit the XRechnung.

4. Use the OZG-RE directory only as a cross-check

Since 19 September 2025 the OZG-RE has been the only federal invoice-receipt platform; the former ZRE was merged into it (opens in a new tab). Its web entry form (Weberfassung) contains a directory of connected Leitweg-IDs, and the federal government also publishes a list of connected public contracting authorities. The federal FAQ nevertheless asks suppliers to use only the ID named when the order was placed. The reason: one authority can have several Leitweg-IDs for separate units, and only the ID from the order routes the invoice to the right budget office. A Leitweg-ID lookup in the directory does not replace checking with your customer.

5. Don't guess

A Leitweg-ID from an old order, from a different office or from a web search may be formally valid and still point to the wrong recipient. The check digit only confirms that the string is internally consistent, not that it belongs to your order. Leitweg-IDs can also change when an authority reorganises its invoice processing. The current order is always what counts.

How public bodies apply for a Leitweg-ID

Only organisations that receive e-invoices apply for a Leitweg-ID. The KoSIT format specification defines only the structure; the federal government and the states handle assignment and maintenance themselves.

Federal authorities

For federal authorities and institutions, and for public contracting bodies connected at federal level, the Zentrales Finanzwesen des Bundes (ZFB) is responsible. Information on applying is available through the contact form on e-rechnung-bund.de. The ID is assigned before the body is connected to the invoice-receipt platform.

Every federal invoice recipient has at least one Leitweg-ID. Further IDs are possible when invoices must reach separate units with their own processing systems. The structure can be changed later, but that means updating procurement documents and informing every supplier. Plan the split in advance, based on how invoices are processed internally.

State and municipal authorities

For state authorities, municipalities and other public contracting bodies in the states, each state designates its own issuing offices. They are listed in the KoSIT overview of the implementation status in the states (Ländersynopse). The coarse address there starts with the state code, followed, depending on the level, by district, county and municipality. Municipalities ask the office their state has designated.

Checklist once the ID is assigned

• Decide responsibilities: which Leitweg-ID belongs to which office or budget unit?
• State the ID in every purchase order and contract, together with the preferred submission channel.
• Publish the ID in your instructions for suppliers.
• If you receive invoices via Peppol: for bodies connected to the OZG-RE, the Peppol ID is "0204:" followed by the Leitweg-ID.
• Double-check every published ID with our leitweg id validator. Single IDs are checked free of charge; bulk validation of many IDs at once is part of the Pro plan.

Where to enter the Leitweg-ID

The Leitweg-ID always goes into field BT-10 (buyer reference, Käuferreferenz). What the field is called depends on the tool:

When you create an e-invoice with our generator, never leave the field empty on an invoice to an authority. If it is empty, the generator falls back to the invoice number so that the file satisfies rule BR-DE-15. For a public body that is not a valid address, and the invoice cannot be routed.

When entering the ID, watch three things: exactly the characters from the order, no spaces before or after, and no added prefixes such as "LW:" or "0204:". Upper and lower case in the fine address do not matter. How to fill in the remaining mandatory fields is shown in our step-by-step XRechnung guide.

Before sending: check the format and check digit

Two quick checks catch most errors before the platform reports them:

1. Check the ID: the Leitweg-ID checker verifies the structure, the allowed characters and the check digit (ISO/IEC 7064 MOD 97-10) and shows the coarse address, fine address and check digit separately.
2. Check the finished invoice: upload the XML file to the xrechnung viewer. It applies the official KoSIT rules and reports, among other things, a missing BT-10 (BR-DE-15).

Every check digit has one blind spot: a shifted hyphen goes unnoticed, because hyphens are not part of the calculation. Compare the position of the hyphens with the order as well. Keep the validation report with the invoice; if questions come up, it shows that the file was formally correct.

Practise with the test ID

For trial runs with the OZG-RE there is a reference environment that requires its own registration. Use the test Leitweg-ID 99661-WEBSERVICEOZG-28 there, or the receiver ID 0204:99661-WEBSERVICEOZG-28 when sending via Peppol. If you are already in contact with a customer, you can also use that customer's Leitweg-ID in the test environment.

Invoice rejected: "Leitweg-ID ist nicht valide" – what now?

The OZG-RE shows this message ("Leitweg-ID is not valid") when it does not accept the ID in the invoice. The federal government names hyphens in the wrong place and spaces before or after the entry as frequent causes. Work through these steps:

1. Check the entry: compare the ID character by character with the order, remove spaces and check where the hyphens are.
2. Test the format and check digit with the validator. If the check digit fails, there is a typing or copying error.
3. Contact your customer and have them confirm that the ID is current and belongs to this order.
4. If you cannot find a solution together, the authority takes the issue to the ZFB. As a supplier you do not have to do this yourself.
5. Create a new, corrected e-invoice and submit it again.

Rejected by the platform or by the recipient?

The OZG-RE distinguishes two cases. Formal errors are detected by the platform itself: with the web entry form and upload channels you see the validation report before sending; for invoices submitted by e-mail or Peppol, a magnifying-glass icon in the invoice overview leads to the details of the formal check. Content errors are found by the recipient, for example when a formally valid but wrong Leitweg-ID has sent the invoice to the wrong unit. The recipient can then leave a reason for the rejection. In both cases you issue a new e-invoice with the corrected data. Other common rejection reasons are covered in how to fix XRechnung validation errors.

B2B: no Leitweg-ID, but still fill in BT-10

Invoices to businesses have no Leitweg-ID. If you send an XRechnung to a business customer, BR-DE-15 still requires a value in BT-10. Enter the reference your customer asks for, such as a cost centre, a project number or the name of the person who ordered. The purchase order number belongs in BT-13. If the customer has not specified anything, ask which reference their invoice approval process needs.

For VAT purposes a missing buyer reference is not a defect. According to the German Federal Ministry of Finance (BMF) letter of 15 October 2025, breaches of business rules that do not concern VAT-mandatory details, such as a missing BT-10, are irrelevant for VAT. The recipient's software will still flag the file as a faulty XRechnung, which can hold up processing. For more on the format, read what is XRechnung? or browse the XRechnung category.