Nearly one in four gas stations puts less gasoline into a car’s tank than the meter indicates—and, of course, than the consumer pays for. This discrepancy results in an additional cost to consumers of 400 million euros per year, according to a study by the National Technical University of Athens (NTUA), and although the rate of non-compliance appears to be lower than in previous years, the numbers are still significant.
The peculiarity of this loophole is that the government profits, as it collects more taxes than what corresponds to actual gasoline consumption. This is because consumers pay for the liters they believe they have put into their vehicles and pay the corresponding tax.
The government’s revenue from all taxes amounts to 36 billion euros, which constitutes half of the budget’s revenue. Of the 36 billion euros, 9.5 billion euros come solely from VAT on petroleum products and the excise tax on gasoline and diesel.
Post-Tax Theft
These taxes account for approximately 60% of the final price. However, the extra tax revenue from a few tampered pumps is very small compared to the tax losses from smuggling, according to the Ministry of Finance.
Suffice it to say that 92% of the industry’s total profits go to the government in the form of excise taxes, income tax, and other levies. The same sources add that the effects of a tampered pump spread like a ripple throughout the market, as quantities appear and disappear out of nowhere.
Comparisons
The question that arises is how, after so many years of the input-output system being in operation—with its parallel upgrades, stricter regulations, and improvements— Greece still ranks, along with Bulgaria and Romania, among the countries with the highest rates of non-compliance within the EU, with 23.1% of gas stations in Attica and 18.8% in Thessaloniki falling short of compliance. This is particularly true when the discrepancies between the actual and theoretical quantities sold reach 15%.
Questions
If we accept that more than 2 out of 10 gas stations in Attica are cheating, as recorded by the National Technical University of Athens (NTUA), then out of the approximately 900 gas stations operating in the Athens Basin, inspectors should have shut down or identified irregularities at more than 200. But the Independent Authority for Public Revenue (AADE) has shut down only 92 gas stations.
The numbers
If we take into account inspections across the entire fuel market—that is, from customs (transport), quality (chemical tests), and the fuel tank (quantity), then in 2025, 16,450 inspections were conducted and 1,403 violations were identified (8.5%). Once again, the violation rate is lower than that indicated by the NTUA study.
How the Cat-and-Mouse Game Is Played
The input-output system plays a central role in the fight against violations. It has been installed at all gas stations for many years, but to date, only about 40%have undergone the mandatory upgrade.
The input-output system is based on the following assumption: Whatever came into a gas station went out. It adds to this the inventory each station may have had prior to being restocked and subtracts whatever remains after closing time.
This data is transmitted to the Independent Authority for Public Revenue (AADE). If everything is done correctly, then the final inventory level should match the amount reported to the AADE. If not, then a chain reaction begins that sets off alarm bells in various parts of the market. Because there’s something left over… And that’s when the audits begin.
Whatever is left over in the “black market”
As senior officials from the AADE’s audit services explain to Euro2day.gr, the inflow-outflow system is the key tool that reveals where there are serious indications of non-compliance. What “spills over” usually ends up on the “black market,” where it will again appear as an inflow somewhere else. Monitoring is needed to identify the “source” that generates “inventory” out of thin air.
Under current legislation, the “warning light” from the electronic inflow-outflow system alone is not sufficient for the Independent Authority for Public Revenue (AADE) to impose penalties or to order the two-year closure of the gas station, according to the new law of 2023.
Cooperation with the “Greek FBI”
For an audit team to proceed to the point of imposing penalties and sealing the gas station, specific steps must be taken, involving the Directorate for Combating Organized Crime (DAOE), also known as the “Greek FBI.”
As soon as a “red flag” is raised and the Independent Authority for Public Revenue (AADE) receives an indication of a possible violation, the Greek FBI is notified, and parallel surveillance and inspection operations begin, involving undercover agents posing as customers—and even as fuel truck drivers.
The goal is to “build a case” with evidence that will “stand up” to challenges and the arguments of the defendants in court. This is because anyone who believes they have been wronged can seek justice through the courts.
Furthermore, the legal framework has been tightened and provides, among other things, for the following: If the same owner operates other gas stations under the same tax identification number (AFM) or holds even a small stake in a similar business, the penalty extends to those locations as well, even if they have not been audited. Consequently, the closure of a gas station can trigger a domino effect of audits and other closures or penalties for many other individuals or businesses, including those affiliated with the owner.
Cases of Organized Crime
A “tampered” pump does not always represent a 1% discrepancy that occurs randomly just once. Experience has shown that such illegal activities often conceal cases of organized crime with many ramifications. There has been a case where a gas station was at the center of an investigation involving dozens of individuals.
Action Plan
For this reason, inspection teams from the Independent Authority for Public Revenue (AADE) or the Ministry of Development are not suited to conduct inspections under the guise of auditors. Special handling is required by the police and the Greek FBI, which monitors the situation and develops an intervention plan to protect the auditors when the time is right, as well as an escape plan for the auditors in case something goes wrong.
A Deep-Rooted Problem
For all these reasons, sources at the Independent Authority for Public Revenue (AADE) report that violations in the fuel trade cannot be addressed in just one or two years, as a large part of the problem is linked to organized crime. “It’s like trying to crack down on organized crime in a single day or a single year,” they say.
Nevertheless, significant improvements have been observed, as violations have decreased by 30% in one year, mainly due to the stricter enforcement of the two-year sealing measure. Similarly, cases of smuggling and general abusive behavior in the sector have also decreased.
Policy Shift
According to government sources, relevant ministries are in discussions to make the system for detecting and cracking down on such cases more effective. One of these areas concerns the legislative framework, with the aim of enabling faster procedures to “resolve” the case. The same sources indicate that discussions are already at an advanced stage, and legislative measures and an update to the AADE’s Strategic Plan are expected soon.
What the Study Shows
Data from the NTUA study, which was conducted using mystery shopping. The NTUA study reports that in Attica, the percentage of deficient deliveries decreased to 23.1% in 2026, down from 33.1% in 2025, while deliveries found to be within legal and/or acceptable limits increased to 76.9%, up from 66.9% last year.
Deviations from the expected quantity reached 14.99% in 2026, compared to 18.2% in 2025—figures that indicate that efforts to combat non-compliance in Attica have yielded significant results, though this does not negate the need to continue inspections.
In Thessaloniki, the results also show an improvement compared to the previous survey in 2025, though to a lesser extent. Both the percentage of deficient deliveries and the magnitude of the deviation remain high.
81.4% of deliveries fell within the legal or acceptable tolerance limits, compared to 80% in 2025, while short deliveries stood at 18.6% in 2026, down from 20% last year. Conversely, there was an increase in deviations from the expected quantity, which reached as high as 14% in 2026, compared to 2025, when the rate was 12.7%.