# Buyer reference and Leitweg-ID problems

The buyer reference, often a Leitweg-ID, routes German public-sector invoices to the correct recipient system.

## What you may see

- Buyer reference is required
- Leitweg-ID is required
- Buyer reference must be between 3 and 50 characters
- Buyer or order reference is required

## What this means

For many German public-sector XRechnung invoices, the buyer reference is the Leitweg-ID. It tells the recipient system where to route the invoice.

## What to check

- Leitweg-ID
- Buyer reference
- Routing ID
- Purchase order number, if the buyer accepts that instead
- Recipient onboarding instructions