E-invoicing has for many years been a central part of digital commerce in Denmark. Today, many companies encounter terms such as NemHandel, OIOUBL, and Peppol in connection with ERP systems, electronic invoices, and new digital bookkeeping requirements.
But what do they actually mean, and how are they connected?
In this guide, we explain what NemHandel and OIOUBL are, how they are used for e-invoicing in Denmark, how integrations and APIs work, and why Denmark is gradually moving from OIOUBL to Peppol standards.
What is NemHandel?
NemHandel is Denmark’s national infrastructure for the electronic exchange of business documents such as invoices, credit notes, and orders.
The system enables companies and public authorities to automatically send and receive electronic documents directly between their finance or ERP systems without manual processes.
NemHandel is primarily used for:
- Electronic invoices
- Credit notes
- Order documents
- Automatic document exchange between businesses and the public sector
When a company sends a NemHandel invoice, the document is sent digitally through the infrastructure directly to the recipient’s system in a standardised format.
NemHandel is administered in Denmark as part of the public digital infrastructure and is already widely used in public e-invoicing.
Although NemHandel has historically been closely associated with public e-invoicing, many private companies also use the infrastructure for automated document exchange between ERP and finance systems.
How does NemHandel work?
NemHandel works as a network that connects companies, ERP systems, and public authorities.
A typical flow looks like this:
- An invoice is created in the company’s ERP or finance system
- The invoice is generated in a standardised electronic format such as OIOUBL
- The document is sent via the NemHandel infrastructure
- The recipient’s system receives and processes the invoice automatically
This means companies can automate large parts of their invoicing processes and reduce the need for manual entry, PDF invoices, and emails.
NemHandel uses registrations via the NemHandel Register, where companies can be found through their CVR number or other identifiers.
In public e-invoicing, EAN numbers are often used to identify recipients and ensure that the invoice is sent to the correct public entity.
What is OIOUBL?
OIOUBL is the standardised Danish format for electronic business documents.
The format is based on UBL (Universal Business Language), which is an international XML standard for electronic document exchange. OIOUBL is the Danish adaptation of this standard and is used, among other things, for e-invoices in Denmark.
The OIOUBL format is typically used for:
- Invoices
- Credit notes
- Orders
- Catalogs
- Other electronic trade documents
When companies send an OIOUBL invoice through NemHandel, the format ensures that the information is structured and can be processed automatically by the recipient’s system.
OIOUBL is XML-based, which means data is structured in fixed fields and tags that systems can read automatically.
Unlike PDF invoices, OIOUBL is machine-readable, which makes it possible for systems to automatically validate, register, and process data without manual entry.
In practice, a real OIOUBL invoice is much more detailed and includes, among other things:
- VAT information
- Payment terms
- Line items
- Item numbers
- Buyer and supplier information
- References and identifiers
The advantage of the OIOUBL format is that data can be read directly by ERP and finance systems without manual processing.
What is the difference between NemHandel and OIOUBL?
NemHandel and OIOUBL are often mentioned together, but they are not the same thing.
In short:
| Term |
Function |
| NemHandel |
Infrastructure/network for document exchange |
| OIOUBL |
Document format for electronic documents |
In other words, NemHandel is the “route” the documents travel through, while OIOUBL is the actual format of the documents.
A company can therefore send an OIOUBL invoice via NemHandel.
NemHandel Integration and API
Many companies today integrate their ERP or finance system directly with NemHandel to automate invoicing processes.
A NemHandel integration makes it possible to automatically:
- Generate e-invoices
- Validate documents
- Send and receive invoices
- Handle receipts and errors
- Synchronise data between systems
Many modern solutions also use NemHandel API connections to automate communication between systems and infrastructures.
This is used, among other things, in integrations between:
- ERP systems
- Accounting systems
- EDI platforms
- Invoicing solutions
- Compliance systems
For companies with large document volumes, automated integrations can significantly reduce manual processes while also improving data quality.
What is Peppol and how is it connected to NemHandel?
Peppol is an international network and standards framework for electronic document exchange.
While NemHandel is primarily designed for the Danish infrastructure, Peppol is used in many European countries and supports cross-border e-invoicing.
Denmark participated early in the development of the Peppol network, and in the coming years Peppol is expected to play a larger role in Danish e-invoicing.
Today, both OIOUBL and Peppol formats can be used in Denmark depending on the solution and the recipient.
OIOUBL vs Peppol
When companies compare OIOUBL vs Peppol, the difference is primarily about standardisation and international interoperability.
| OIOUBL |
Peppol BIS |
| Danish document standard |
International document standard |
| Used primarily in Denmark |
Used in many European countries |
| Based on UBL |
Based on UBL |
| Often exchanged via NemHandel |
Exchanged via the Peppol network |
| Planned gradual phase-out |
Future strategic standard |
Denmark plans to gradually phase out OIOUBL in favour of Peppol BIS 4 (PINT) between 2028 and 2029.
The goal is to create better international compatibility and support future EU requirements for digital invoicing.
The Future of OIOUBL and NemHandel in Denmark
The Danish Bookkeeping Act and upcoming EU initiatives such as ViDA (VAT in the Digital Age) are already influencing developments in e-invoicing.
Denmark already has mandatory requirements for public e-invoicing (B2G), while there is not yet a general mandatory requirement for B2B e-invoicing. However, the trend points toward more digital requirements in the coming years.
This means companies should increasingly prepare for:
- More requirements for digital invoicing
- Integration between ERP systems and e-invoicing networks
- Increased use of Peppol standards
- Automation of compliance and document exchange
For many companies, e-invoicing is therefore no longer just a compliance requirement, but an important part of a modern digital supply chain.
Benefits of NemHandel and OIOUBL
For many companies, electronic invoicing is not just about compliance, but also about making processes more efficient and automated.
Some of the benefits of NemHandel and OIOUBL include:
- Less manual data entry
- Faster invoice processing
- Fewer errors in document handling
- Better compliance and traceability
- Automation between ERP and finance systems
How can TrueCommerce help with NemHandel and OIOUBL?
At TrueCommerce, we help companies automate electronic document exchange through integrations, EDI, and e-invoicing solutions.
With integrations for ERP and finance systems, your company can manage:
- NemHandel integration
- Electronic invoices
- OIOUBL and Peppol formats
- Compliance requirements
- Automated document exchange
This makes it easier to scale digital processes and prepare for future e-invoicing requirements.
Frequently asked questions about NemHandel and OIOUBL
What is NemHandel?
NemHandel is Denmark’s digital infrastructure for the electronic exchange of documents such as invoices, credit notes, and orders.
What is OIOUBL?
OIOUBL is the Danish XML-based format for electronic business documents and is used, among other things, for e-invoices.
Is OIOUBL the same as Peppol?
No. OIOUBL is a Danish document standard, while Peppol is an international network and standards framework for electronic document exchange.
What is NemHandel used for?
NemHandel is used for the automatic exchange of electronic documents between companies and public authorities.
How does an OIOUBL invoice work?
An OIOUBL invoice is structured in XML format so ERP and finance systems can automatically read and process the data.
Is NemHandel mandatory?
NemHandel is mandatory for many public e-invoicing processes in Denmark, but general mandatory B2B e-invoicing has not yet been introduced.
When will OIOUBL be phased out?
Denmark plans to gradually phase out OIOUBL between 2028 and 2029 in favour of Peppol BIS 4 (PINT).