What is the Online Invoice Reporting System?
The Online Invoice Reporting System (Hungarian: Online Számla Rendszer) is a digital platform launched in 2018 by the Hungarian Tax and Customs Authority (NAV). It enables real-time electronic transmission of invoice data from invoicing software to NAV. The system was designed to strengthen VAT (Value Added Tax) monitoring, reduce tax evasion, and ease the administrative burden on businesses.
As of January 4, 2021, its use is mandatory for all domestic taxpayers under Annex 10 of the Hungarian VAT Act (Act CXXVII of 2007).
What legal obligations does the system impose?
Under Annex 10 of the VAT Act, taxpayers must report the following to NAV:
- Every invoice issued to another domestic taxpayer,
- All product sales and service provisions,
- Any documents equivalent to invoices (e.g., corrections, cancellations).
This ensures that NAV receives near real-time data on all domestic economic activities, greatly increasing transparency and auditability.
How is the Online Invoice System structured?
The system consists of two main components:
Web interface
Allows manual data entry, invoice review, error logs, technical user creation, and system management.
Machine-to-Machine (M2M) interface
Enables automated data transmission from invoicing systems without human intervention. Communication occurs in structured XML format following NAV’s official schema.
Using the M2M interface is now considered standard for professional invoicing environments.
What data must be submitted?
The following data must be sent:
- Supplier and customer details (e.g. tax number, company name),
- Invoice number, issue date, and performance (delivery) date,
- Itemized invoice lines (description, quantity, net amount, VAT),
- Payment method and deadline,
- Reference details in case of corrections.
Important: NAV does not receive the invoice image or PDF – only the structured data in XML format.
What systems can be integrated?
The system accepts data from:
- Custom-developed invoicing software,
- Enterprise ERP systems (e.g. SAP, Microsoft Dynamics),
- Cloud-based invoice providers (e.g. Billingo, Számlázz.hu),
- Any software compliant with the NAV XML schema and with a technical user.
Integration requires creating a technical user via the web interface, which the invoicing system uses for authentication.
What are the benefits of the Online Invoice System?
Although mandatory, the system offers practical advantages:
- Automated reporting reduces manual tasks,
- Instant feedback on errors improves data quality,
- Enables a transparent and real-time invoicing environment,
- Facilitates the transition to e-invoicing, especially through NAV eInvoice.
Summary
The Online Invoice Reporting System is NAV’s digital VAT control infrastructure that mandates real-time invoice data submission between VAT-registered entities. With both web and M2M interfaces, the system ensures that invoicing software can transmit data directly to NAV. It benefits not only tax authorities but also businesses, offering faster, more accurate, and more transparent invoice management.
Official definition
The Online Invoice System is a digital platform operated by NAV since 2018 for the real-time submission of invoice data. It supports data transmission via a web interface or machine-to-machine (M2M) connection and is designed to fulfill Hungary’s online invoice reporting obligations.
Related Services
Accounting and Tax automation
The expertise and relevant tools of our tax technology team can help you ensure compliance with the applicable legal provisions while keeping your existing software.
NAV Online Invoice administration
Our automated solution can be an advantageous alternative to manual subsequent data reporting performed on the NAV Online Invoice portal.
NAV Online Invoice audit simulation
Our automated solution can be an advantageous alternative to manual subsequent checks performed on the NAV Online Invoice portal.
Creating a data connection
Many ERP systems are not equipped to access the digital services provided by NAV. While the immediate and automatic reporting of all invoices issued is a legal requirement.