E-invoicing: technical implementation in Lexware Office
This guide explains which formats the programme supports, how to create e-invoices, how to record incoming ones, and how to submit the documents to us.
Introduction
If you use Lexware Office (formerly lexoffice), you are well-equipped for e-invoicing. The programme creates structured invoices, sends them, receives incoming e-invoices and extracts their data for accounting purposes. We work together to ensure this runs smoothly and handle the tax processing.
A few points to clarify beforehand: you will hardly need to change your workflow at all. You create invoices in exactly the same way as before; the programme determines whether an invoice becomes an e-invoice based on the data on file.
There is one prerequisite: the e-invoicing function must be activated once, and the customer must be set up as a company contact with complete details. Only then will Lexware Office automatically generate an e-invoice.
This article follows the structure of all our tool guides: first, what the tool can do; then the formats; next, the steps for creating and receiving e-invoices; finally, potential sources of error, handing over to us, and frequently asked questions.
What Lexware Office can do
Lexware Office is a comprehensive solution with its own accounting module. The programme can create, send, receive and process e-invoices for accounting purposes.
Upon receipt, the programme extracts the structured data and uses it to pre-fill the document entry. Unlike a pure invoicing programme, the process does not end with archiving, but feeds directly into the accounts.
| Function | Is this possible in Lexware Office? |
|---|---|
| Create e-invoices | Yes, XRechnung and ZUGFeRD |
| Send e-invoices | Yes, directly from the programme or via your own email client |
| Receive e-invoices | Yes, upload with validation |
| Extract and process data | Yes, automatic capture for accounting |
Which formats Lexware Office supports
Lexware Office generates both formats commonly used in Germany – XRechnung and ZUGFeRD. From the tax authorities’ perspective, both comply with the required European format.
The programme determines which format to generate based on the contact. If the customer is a business contact, Lexware Office automatically creates a ZUGFeRD invoice. If the customer is a public authority and the routing ID and supplier number are on file, an XRechnung is generated.
In the case of a ZUGFeRD invoice, the XML file is integrated into the visible PDF. Even if only the PDF is displayed to you, the invoice is considered an e-invoice. We will discuss the differences between ZUGFeRD and XRechnung separately. \[Link zu einem Hilfsartikel]
Enable the e-invoice function
Before you create e-invoices, you need to activate the function once. It is available from version M onwards.
To do this, go to the settings via the cog icon and enable e-invoicing there. You should also enter your full company details – address, tax number or VAT registration number and federal state – as these are included in every e-invoice.
Create an e-invoice
Word-for-word transcript
To create an e-invoice with Lexware Office, we first need to enable the feature in the settings. To do this, we click on the cog icon in the top right-hand corner and select ‘E-invoice’.
Here, we can enable e-invoicing.
We can then create a new invoice in the dashboard as usual.
We select the customer and, under ‘Edit’ and ‘E-invoice’, we can enter a supplier number for this customer or the routing ID, which is mandatory for an x-invoice.
I’ll pause here for a moment. Let’s fill in the rest of the invoice. I’ll use a sample item here.
We can now proceed to the preview, where you’ll see confirmation that you’re creating an e-invoice. If any details are still missing, you’ll be presented with a checklist here that you can work through.
We now have the option to send the e-invoice directly from Lexware Office via email, or to finalise and print it, or finalise and save it.
Here, in the document format, you’ll also see confirmation that you’ve created a PDF transport invoice. If we open the document, a standard PDF is displayed, which incorporates an XML file.
Once activated, you can create e-invoices as usual. A checklist helps you to add any missing details.
-
Open the document editor
Go to ‘Documents > New Document > Invoice’ or, in the dashboard, click ‘New Invoice’. Alternatively, use the plus sign in the top bar.
-
Select the company contact
Select the customer as the company contact with their full billing address. For a public authority, enter the routing ID and supplier number provided by your customer in the contact details.
-
Enter the line items
Add the invoice items. Ensure all details are complete so that the invoice meets the requirements for an e-invoice.
-
Check the checklist
The preview displays a checklist showing whether all the necessary information has been entered. If anything is missing, add it. Once all requirements have been met, a message appears stating that an e-invoice is being generated – either as a ZUGFeRD or XRechnung, depending on the contact.
-
Finalise and send
Select ‘Finalise & Save’ and send the invoice directly from Lexware Office or via your own email programme. The e-invoice is sent as an attachment – as a PDF for ZUGFeRD or as XML for XRechnung.
If you send the invoice via your own email programme, check – for ZUGFeRD – that the machine-readable XML section is included in the PDF. You can verify this in Adobe Reader or Mozilla Firefox, for example. For the tax office, only the XML counts; a PDF without an embedded data record is not an e-invoice.
Note on attachments
There is an important restriction regarding attachments with e-invoices. With neither ZUGFeRD nor XRechnung can additional files be embedded within the invoice file itself.
In the ZUGFeRD format, you can send additional files alongside the email, but they do not become part of the invoice file and cannot officially be treated as part of the e-invoice. In the XRechnung format, attachments are not permitted at all. Mandatory information must therefore always be included in the invoice itself, not in an attachment.
Recording incoming e-invoices
Word-for-word transcript
To process incoming e-invoices in Lexware Office, we create a new document as usual. We can now drag and drop an e-invoice into this window. This is an example XML invoice.
And you can see that Lexware Office automatically displays the data.
The supplier, document number, document date and due date are entered automatically. You can now categorise the document and close the document window. Transport invoices are entered using the same principle. We create a new document and drag the invoice into this window.
We categorise and save it.
You upload incoming e-invoices as before. Lexware Office recognises the format and extracts the data.
-
You upload the invoice
You import the received e-invoice just like any other document. During the upload, the system checks for technical validity – outdated or incorrect e-invoices are rejected by the system.
-
The programme extracts the data
For XRechnung and ZUGFeRD in accordance with EN 16931, the content is extracted from the XML file. In the case of a ZUGFeRD file with incorrect XML, the PDF image is used on a temporary basis for content recognition.
-
You complete the entry
The extracted data pre-fills the document entry form. This does not change your workflow; you can still upload standard PDF, JPEG or PNG documents.
Handover to us
Even though Lexware Office has its own accounting system, we coordinate our collaboration with you – for example, via access to your Lexware Office account or via the agreed document routing process.
Common sources of error
- Function not activated: E-invoicing is expected but has not been activated. Unless activated via the settings icon and from version M onwards, the programme will not generate an e-invoice.
- Customer not set up as a company: The contact is registered as a private individual. Lexware Office will then not generate an automatic ZUGFeRD invoice.
- Routing ID missing for public authorities: An invoice for a public authority is created without a routing ID and supplier number. In this case, an XRechnung cannot be generated.
- XML section missing when sending via own email programme: The ZUGFeRD PDF is sent via the user’s own email programme without the embedded XML section. For the tax office, only the XML counts.
- Mandatory information moved to an attachment: A required piece of information is sent as a separate attachment. Attachments are not part of the e-invoice; mandatory information must be included in the invoice itself.
- Only the PDF is submitted: The visible PDF is used for submission to us. We require the structured data.
How we work together
With Lexware Office, you create and enter the invoices; we handle the tax processing and classification.
Your tasks:
- Activate the e-invoice function and ensure master data is fully maintained
- Create and send e-invoices, and record incoming ones
- Make the structured data available to us via the agreed method
Our tasks:
- Review and classify the accounts for tax purposes
- Provide support with set-up and formatting issues
We will agree the exact breakdown with you.
Frequently asked questions
Can Lexware Office create and receive e-invoices?
Yes. Lexware Office creates, sends, receives and processes e-invoices. Unlike a dedicated invoicing programme, it has its own accounting module and extracts incoming data for document entry.
Which formats does Lexware Office support?
XRechnung and ZUGFeRD. ZUGFeRD is automatically generated for business contacts, whilst an XRechnung is generated for public authorities with a registered routing ID and supplier number.
Do I need to enable anything?
Yes. The e-invoicing function is available from version M onwards and must be activated once via the cog icon in the settings.
Why isn’t Lexware Office creating an e-invoice for my customer?
Often, the contact is not set up as a company, or required details are missing. For public authorities, the routing ID and supplier number must also be on file. The checklist in the preview shows what is missing.
How can I tell if my ZUGFeRD PDF contains the XML section?
You can check whether the PDF contains an XML attachment in programmes such as Adobe Reader or Mozilla Firefox. For the tax office, only this XML section counts.
Can I add attachments to the e-invoice?
Not within the invoice file itself. With ZUGFeRD, you can send additional files via email, but they are not part of the e-invoice. XRechnung does not support attachments.
Are incoming e-invoices automatically posted?
The data is extracted and used to pre-populate the document entry form. The final tax classification is carried out in collaboration with us.
How do my Lexware Office documents reach you?
Via the agreed method – such as access to your account or the agreed document routing process. It is important that the structured data reaches us. \[Link zu einem Hilfsartikel]
Legal notice
This article provides an overview and does not replace individual advice. The scope of functions, version levels and menu navigation in Lexware Office may change as a result of updates; the current status of the software and the legal situation at any given time shall prevail.
If you have any questions regarding the set-up or transfer of your documents, please contact us directly.
As at: June 2026