As of 15 September 2025, the Hungarian Tax Authority (NAV) has tightened the validation rules for online invoice data reporting. Fifteen former WARN messages have been reclassified as ERROR, meaning that affected issues – such as incorrect customer codes, inaccurate tax numbers, wrong performance dates or exchange rates, and improper use of VAT exemption or out-of-scope references – now qualify as failed submissions. Detailed technical documentation is available on NAV’s GitHub page.

According to NAV, the reclassified errors previously affected nearly one million submissions per month. After the announcement, taxpayers and software developers took action, which led to a steady decrease in the number of warnings. The aim is to improve tax digitalisation and data quality, particularly in preparation for the implementation of the eVAT (eÁFA) system.

 Deadlines and Penalties

NAV has made it clear that there is no grace period: the new rules apply from 15 September 2025, and the test environment has been available since 1 September. Failure to submit, or submitting incorrect invoice data, may result in a penalty of up to HUF 1 million per invoice.

Other Changes and Future Outlook

• Domestic summary report (Form “M”): From 31 July 2025, taxpayers may voluntarily provide the deductible net and VAT amounts on received invoices, alongside the total net and VAT, helping with more accurate data matching between invoices and returns.
• eVAT (eÁFA) system: New data fields in the ÁNYK VAT return bring it closer to the eVAT system; the date when filling these fields becomes mandatory will depend on legislative decisions.
• ViDA and e-invoicing: By 2030, under the EU’s VAT in the Digital Age (ViDA) package, e-invoicing (Digital Reporting Requirements – DRR) will become mandatory across the EU, and Hungary is expected to require B2B e-invoices domestically as well. The current PDF-based practice is likely to be replaced by the EU-standard XML e-invoice format.

MGI-BPO Advisory Services

Keeping up with frequent changes in Hungarian tax and reporting regulations requires expertise and up-to-date solutions. The MGI-BPO team supports clients with comprehensive tax and accounting services, as well as professional advice to ensure compliance and optimise processes.