Luxembourg collected €29.178m in late-payment interest in 2025, according to finance minister Gilles Roth (CSV). The figure marks a continued recovery in late-payment interest receipts after a sharp decline in 2022, with individuals accounting for the larger share of the latest total.

Moreover, companies remain less likely than individuals to file their tax returns on time. At the beginning of January 2026, almost one in five companies had still not filed their 2024 return, compared with about one in ten individual taxpayers.

The legal deadline for income tax returns is currently set at 31 December of the year following the tax year concerned, Roth stated.

For the 2024 tax year, the Luxembourg Inland Revenue (ACD) recorded a higher filing rate among individuals than among companies. Roth added that the available data for recent tax years showed relatively stable compliance, with average on-time filing rates of 88.6% for individuals and 81.3% for companies.

Reform impact

The government cannot conclusively assess whether extending the filing deadline has changed taxpayer behaviour. Roth stated that the ACD’s IT system does not allow historical data to be extracted on filing rates within legal deadlines. The available statistics are based on manual extractions carried out after the deadline was extended.

In the absence of comparable pre-reform data, Roth concluded that it is not possible to determine the concrete effects of the longer legal deadline on taxpayers’ filing behaviour.