The NAV Data Reconciliation procedure: risk or opportunity?

The NAV Data Reconciliation Procedure – Cooperation before audit

In recent years, the audit practice of the NAV has undergone significant transformation. With the advancement of digitalisation, online data reporting and risk analysis tools, the authority has increasingly shifted its focus toward prevention and cooperation.

One of the most important instruments of this new approach is the data reconciliation procedure introduced from 2025, which opens a new chapter in the relationship between NAV and taxpayers.

 

What is the Data Reconciliation Procedure?

The data reconciliation procedure is one of the least severe forms of official procedure applied by NAV. Its purpose is not to impose sanctions, but to clarify discrepancies between the data available to the tax authority and the taxpayer’s filed returns and reports.

The legal basis of the procedure is set out in the Act on the Rules of Taxation. Its essence is that NAV selects a narrow group of taxpayers through a thorough filtering process and provides them with the opportunity, via a dedicated interface on the Client Portal, to clarify the reason for the discrepancy by answering a few questions.

Taxpayers may indicate, for example, that the error has already been corrected, that a self-revision tax return has been submitted, or that in their view the discrepancy is not valid and the indicated error does not exist.

The procedure is conducted entirely electronically. The taxpayer must respond within 15 days of receipt of the notification and declare the reason for the discrepancy, and, if necessary, correct the relevant data.

In what areas does NAV initiate Data Reconciliation Procedure?

The focus of data reconciliation is primarily on data that NAV receives online and in real time, and which it can compare with taxpayers’ returns, as well as on potential logical inconsistencies identified within the data reported in returns.

Data reconciliation most commonly occurs in the following areas:

• discrepancies between online invoice reporting and VAT returns (especially the data in the VAT return annexes detailing supplier invoices),
• differences between online cash register data and reported revenue,
• inconsistencies between employment registrations and social security contribution returns,
• specific sectoral or campaign-based reviews (e.g. zero VAT returns submitted alongside reported revenue),
• calculation of self-revision penalties,
• compensation surcharge,
• discrepancies between corporate income tax (CIT) returns and the annual financial statements,
• late submission of VAT returns,
• and similar types of inconsistencies.

 

It is important to emphasise that a discrepancy does not automatically imply a legal violation. In many cases, the background is a technical issue or a timing difference.

For example, in the case of a self-revision, NAV generally calculates the self-revision penalty according to the standard rules. If a lower amount of penalty is declared in the return compared to NAV’s calculation, a data reconciliation procedure may be initiated.

The discrepancy may, however, be entirely lawful. If the self-revision does not result in an additional payment obligation-because the taxpayer already settled the liability by the original deadline or in the course of a previous self-revisionbthe penalty must be calculated according to the general rules, but in the case of private individuals only up to HUF 1,000, and in the case of other taxpayers up to HUF 5,000, must be declared and paid.

Such discrepancies can be clarified conveniently and efficiently within the framework of the data reconciliation procedure.

Why is the Data Reconciliation Procedure beneficial for NAV?

For NAV, the data reconciliation procedure is an efficient, resource-saving tool. It enables the authority to:

• focus audit capacities on genuinely high-risk or fraudulent cases,
• resolve simpler discrepancies quickly and in an automated manner.

This procedure aligns well with NAV’s modern, partner-oriented approach to tax administration.

Why Is Data Reconciliation beneficial for the company concerned?

From the taxpayer’s perspective, the data reconciliation procedure is clearly advantageous. Its advantages include:

• compliant taxpayers can avoid lengthy audit procedures,
• it does not qualify as a traditional tax audit,
• it does not involve the imposition of tax penalties or tax deficiency assessments,
• the taxpayer can correct errors independently and under controlled circumstances,
• the process is fast, transparent and handled electronically.

In this sense, data reconciliation functions as a form of “warning and opportunity” that supports voluntary compliance.

 

What are the possible legal consequences?

If the taxpayer responds within the deadline and clarifies the discrepancy, the procedure may be closed without legal consequences. NAV imposes sanctions only if the taxpayer fails to respond within 15 days of the notification.

In such cases, a fine of HUF 300,000 may be imposed, and NAV may subsequently initiate a tax audit.

The emphasis is therefore clearly on cooperation and timely response.

 

Overall, the Data Reconciliation Procedure Is not a problem, but an opportunity – for both the taxpayer and the accountant

 

From a professional perspective, the initiation of a data reconciliation procedure carries a positive message. It indicates that the client and their accountant fundamentally belong to the compliant category, where NAV first seeks clarification rather than immediately launching an audit.

A well-prepared accounting firm can respond to a data reconciliation notice quickly and professionally by comparing the relevant data sources and tax returns, and by providing a professionally substantiated response within the deadline. This:

• reduces the client’s risks,
• helps avoid a later, significantly more burdensome tax audit,
• and contributes in the long term to maintaining the client’s reputation as a “reliable taxpayer.”