Everything you need to know about e-invoicing

Deutsche Telekom will be gradually switching to the legally required e-invoicing system by the end of 2026. From 1 January 2027, we are obliged to send invoices to business customers exclusively in e-invoice format. With this change, we are complying with the legal requirements for digital and audit-proof invoices, whilst at the same time offering you greater efficiency and transparency in your business processes.

Migration process:
• All business customers affected by the migration will be informed of the migration and the process in good time before it takes place.

• Your email address is essential for the successful delivery of your e-invoice. Once your email address has been verified, you will be ‘e-invoice ready’ and the migration can be carried out without any problems.

• Until June 2026, you will receive your e-invoices in both XML and PDF formats. Over the course of 2026, we will gradually switch to the ZUGFeRD format (UBL/XML with a PDF component).

Your part in ensuring a successful transition:
• A successful migration is only possible if we have the correct and unambiguous email address of your invoice recipient and its verification status. You can enter this information in the MBSP portal. Missing or unclear details are the most common cause of delays.

• Please make use of the options set out in our information letter for the verification and allocation process. We will send you the information letter before the changeover.

With the Growth Opportunities Act (27 March 2024; Federal Law Gazette I 2024 No. 108) and in accordance with European requirements (EU Directive 2014/55/EU, European standard EN 16931), the Federal Government has decided to gradually make e-invoicing mandatory for businesses. The aim is the complete digitisation and standardisation of the invoicing process in Germany.

More on the Growth Opportunities Act

: Telekom is currently running a project to implement this requirement. The changes will be rolled out across the various products and tariffs in 2026. We will inform you well in advance of when the billing for your tariffs and products will switch to e-invoicing.

In accordance with legal requirements, Telekom will switch to electronic billing (e-billing) by the end of 2026. As part of this process, the provision of paper bills – including all attachments such as itemised bills – will be discontinued for business customers.

You will be informed in detail in advance about the planned changeover. If you are currently still receiving paper invoices and have not provided a verified email address for invoices, you will be contacted from March 2026 to verify your invoice email address and link it to your billing account. 

A digital bill, whether as a PDF or sent by email, is identical to a paper bill. It is recognised for tax purposes and can be accessed online for up to 18 months. It is available to both private and business customers. Bills are sent only to verified email addresses; the itemised bill (EVN) can only be accessed via the Customer Centre, not by email. For business customers, machine-readable formats (CSV/XLS) are available as an option for analysis. It is environmentally friendly and digitally available at all times; for many tariffs, no additional request is required.

An e-invoice is a structured, machine-readable invoice format (usually XML) that complies with the European standard EN 16931.

This format enables end-to-end digital processing, for example for accounting or ERP systems.

The content and structure of e-invoices are strictly defined – that is, they are regulated by law or in accordance with specific standards (for example, the XRechnung standard for German public authorities). In most cases, e-invoices are made available via specialised portals or transmission channels, such as the ZRE portal for public contracting authorities.

E-invoicing is primarily aimed at business customers and public authorities. It is not simply a PDF, but a structured XML format that can be processed automatically.

Once you have switched to e-billing, you will be able to manage the BT (Business Term) fields for mobile services yourself in MBSP. This is not yet possible for internet and landline contracts.

 Go to the MBSP login page

When setting up a new e-invoicing account, two pieces of information are particularly important:
•BT49: the recipient’s email
address•BT10: the routing ID (this field is set to
‘not specified’ by default)

These fields must be completed correctly to ensure that the electronic invoice can be delivered and processed properly.

Depending on the sector, additional details may be included in the e-invoice. For the mass market (mobile telephony / internet & landline), the following BT fields are available:

•BT13: Customer’s
internal order number•BT29: Telekom identifier in the customer’s system•BT56
: AsP invoice at the
customer’s end•BT57: Telephone number associated with the AsP invoice at the customer’s
end•BT58: Email address of the contact person for the invoice at the customer’s end

For the individual market (ITInhouse, ÜW, SAP, BRIM), the following can also be used:
•BT11: Project
reference•BT19: Customer accounting
reference•BT23: Business process type

These fields are optional, but they help to organise invoices more easily and automate internal processes within the company.

In accordance with EU standard EN 16931, invoice formats depend on the type of recipient and the organisational structure.
Public sector contracting authorities (the federal government, the Länder and local authorities) use XRechnung – the electronic invoice for public authorities.

- Electronic invoicing for public authorities –
E-invoicing in the federal administration

Business customers are gradually making the transition to the full e-invoicing requirement.

Deutsche Telekom supports various standardised formats, including: EDIFACT (Electronic Data Interchange for Administration, Commerce and Transport) – a well-established format in the B2B sector, particularly for structured invoice data in electronic data interchange.

ZUGFeRD (PDF/A-3 with embedded XML-CII) – also available as an e-invoice format from the end of 2026.

We therefore offer you, as a business customer, a flexible range of formats to ensure a seamless and legally compliant transition to e-invoicing.

An XML invoice (often referred to as an XRechnung or e-invoice) is a structured, machine-readable data format that stores invoice data in XML tags (Extensible Markup Language) rather than as an image (such as a PDF). It enables automated processing in accounting software without the need for manual data entry.

BMI information on e-invoicing 

A ZUGFeRD invoice is a hybrid electronic invoice format that combines a human-readable PDF with structured XML data (CII format) in a single file (PDF/A-3). It enables automated processing in accounting systems, complies with e-invoicing standards (EU Standard 16931) and is ideal for the electronic exchange of invoices in the B2B, B2G and B2C sectors. Telekom plans to introduce it in the middle of the year.

BMI information on ZUGFeRD

Everything you need to know about ZUGFeRD

For mobile services, the change can be made via your MBSP portal or through our customer service team.

For landline and internet services, please contact our customer service team.