This blog was last updated on April 3, 2025
As governments worldwide continue to shift to Continuous Transaction Controls (CTC) systems, such as e-invoicing and real-time e-reporting, another trend organically unfolds as part of this move towards tax digitisation: pre-filled returns.
With access to real-time transactional level data – and other types of data, such as payroll, inventory and other accounting data transmitted at less regular intervals – tax authorities can facilitate other tax obligations with measures like prepopulating returns. This move ensures that the data submitted via CTC systems become the taxpayer’s single source of truth and highlights the importance of data quality.
Countries such as Chile – the cradle of e-invoicing – along with Indonesia, Spain and Portugal, have now been using pre-filled returns for several years. Many other countries have followed suit, with Greece being one of them.
Pre-filled VAT Returns in Greece: Overview
Greece made this significant step in 2022, introducing a new framework for pre-filled VAT returns based on data submitted through the myDATA platform. The measure aims to increase accuracy, transparency, and administrative efficiency for both businesses and tax authorities.
Greece has also made the pre-filing of income tax returns, namely the Statement of Financial Data from Business Activity (Form E3) based on myDATA, available.
As this framework evolved, Greece made another move. The country’s tax authorities set limits to the adjustments taxpayers could make to pre-filled returns, essentially locking the declarations to a certain extent. Since 2025, a zero-deviation limit has been reached for pre-filled VAT returns, while a more flexible cap is currently in place for Form E3. However, this is also expected to be gradually reduced over time.
What Are Pre-Filled VAT Returns?
Pre-filled VAT returns are VAT declarations that are automatically populated using data transmitted to the digital bookkeeping platform, myDATA. Rather than manually entering figures into the VAT return, taxpayers see their returns pre-filled with data based on their invoices and expense records submitted through CTC regimes.
Under this model, the VAT return becomes effectively “locked”. Taxpayers can no longer freely adjust revenue and expense fields. If discrepancies are identified, businesses must correct the data directly within myDATA to ensure the return reflects accurate information.
Key Regulatory Provisions
Ministerial Decision 1020/2024 is the regulation that outlines the rules governing how submitted myDATA data impacts pre-filled VAT returns, sets the limits on allowable deviations and the procedures for handling correlation difficulties.
The regulation introduced two core compliance rules:
- Revenue Rule: VAT returns cannot report income that is less than what has been transmitted to myDATA. Overreporting is allowed.
- Expense Rule: VAT returns cannot report expenses that exceed what has been transmitted to myDATA. Underreporting is allowed, including cases where the taxpayer voluntarily chooses not to deduct certain expenses.
Tolerable Deviation Thresholds
The regulation sets temporary thresholds for deviation between declared amounts and those submitted via myDATA to provide transitional relief from the revenue and expense rules. These are called tolerable deviation limits.
The initial rule allowed taxpayers to adjust their income and expenses by up to 30%. However, over time, the limits were gradually reduced. Since January 2025, the threshold has dropped to 0%, which means that there is no possibility of deviating from the amounts locked in the pre-filled return by myDATA under the revenue and expense rules.
Deadline for Corrections
One of the most important compliance aspects is the deadline for updating data in myDATA. Corrections must be made before the submission deadline of the VAT return for the relevant period. After that, the return is locked, and any subsequent changes would require the filing of an amended VAT return.
Pre-Filled Income Tax Returns
Since the 2023 tax year, Form E3 has been pre-filled based on data submitted to myDATA by taxpayers. However, from the 2024 tax year onwards, taxpayers may only modify these pre-filled amounts within certain limits.
According to new rules introduced in March 2025, a 30% deviation limit is established for revenue and expense data reported in Form E3, per tax year, in relation to the corresponding myDATA-reported values.
In addition to deviation limits, the new rules regulate aspects such as the classification of income and expenses, the mandatory reconciliation of reported data with myDATA records and the procedures for handling discrepancies in pre-filled amounts.
However, following the trend seen with VAT returns, deviation limits for Form E3 are expected to be gradually reduced until it is no longer possible to change the pre-filled amounts under the revenue and expense rules.
How to Ensure Compliance?
The move to pre-filled returns represents a broader shift toward real-time, data-driven compliance in Greece. While the framework introduces new responsibilities for taxpayers, it also simplifies the return process and reduces the risk of human error.
With tolerable margins eliminated for VAT returns – and further tightened for Form E3 – businesses should focus on proactive data management to fully benefit from the efficiencies of the new system.
To remain compliant and avoid discrepancies in their VAT returns, businesses operating in Greece should:
- Ensure timely and accurate transmission of all invoices and expense data to myDATA.
- Regularly reconcile internal accounting systems with myDATA entries.
- Address any correlation difficulties early and document the reasons.
- Stay informed about the eliminated and shrinking deviation thresholds and prepare for full alignment.
For businesses already familiar with digital reporting under myDATA, the transition should be smooth, but for others, now is the time to prepare.
