Buying a coffee very early is often the first thing a frontier worker does when he thinks he has to justify his presence at work or at least in Luxembourg. (Photo: Shutterstock)

Buying a coffee very early is often the first thing a frontier worker does when he thinks he has to justify his presence at work or at least in Luxembourg. (Photo: Shutterstock)

Remote work makes it more difficult for cross-border workers to prove that they haven’t exceeded the maximum number of days worked from home to the tax authorities in their country of residence. Apart from a bundle of presumptions that is deemed admissible, time clocks are needed.

In France and Belgium, taxpayers have to gather proof when questioned by tax authorities. And while the decrees implementing the tax treaties between Belgium and Luxembourg or between France and Luxembourg are very similar, they have become outdated with the development of teleworking and border offices. That is especially true in a context where a day started or finished at home is counted as a full day of remote work.

An annual or monthly train pass for instance is not a guarantee that the employee uses it to go to the office every day. A restaurant bill or a parking ticket does not ensure that the employee has started their working day in Luxembourg. Nor does an access system to a workplace say whether the worker actually spent the day in the office working or whether they did not leave five minutes or an hour later. 

Many different situations

Even the mileage of their vehicle, whether personal or company-owned, does not count as proof that the employee used it to travel between their home and their place of work. Those who have to travel, even in Luxembourg, between several clients, between a head office and a client, etc cannot be forgotten. Minutes of meetings also only work if they are recorded in detail every day. 

So what can employees do to prove their good faith? 

"At home," explains an employee of a Big Four company who wished to remain anonymous, "Belgians go and buy a coffee in the morning, then a newspaper, and keep their parking tickets. Recently, the Belgian administration refused a badge statement.” Other companies, like PwC, refuse to answer the question of what system is in place for employees to be able to justify their presence in the office. 

A 2017 law requires companies to keep "a special register or file of the start, end and duration of daily work as well as any extensions to normal working hours, hours worked on Sundays, statutory holidays or at night".

Five years later, companies are far from complying with this obligation. 2021 was even a record for the labour and mines inspectorate, which pointed out 361 companies that were not in order. This has been the second highest number of violations recorded by the ITM for the past five years.

DSK to the rescue of employees

There are, however, some forty technologies that are marketed in Luxembourg--‘time clocks’ as they used to be called in the industry.

The state uses the Interflex system, which processes the data of 5 million employees in the countries where it has been introduced. The company is originally from Germany and was bought ten years ago by the Belgian company Allegion. The problem is that its flexibility works against it as it is not used in a homogeneous way by all state entities.

According to the ministry of digitalisation, the ministry of civil service is working on a centralised time management system which, once validated, should be deployed in all ministries and all administrations, in order to have information on the rate of teleworking, on leave or the rate of absenteeism.

One floor below and like "many companies", according to one of its managing directors--Thierry Krombach--most municipalities use the Luxembourg SME DSK Systems, which employs 32 people and has a turnover of €3.5m per year.

Its product, , based on the TiM software, allows, in the context of telework, the employee to ask to telework. Their manager can then accept or not the request. It also lets team managers specify who is teleworking and who is "in the office", as well as order an individualised export of the hours spent teleworking or in the office. The PresAbs function allows employees to be distinguished between the two categories. For companies with satellite offices, a mobile time clock can be installed in the satellite office and the clocking in and out is geolocated. The system also applies to mobile workers.

ProTime, Gesper and 36 solutions

SD Worx markets Protime. is a solution that, among other things, makes it possible to track the movements of personnel. "This enables us to identify the country in which the employee has worked and therefore to collect valuable data for tax purposes by checking the number of hours worked in Luxembourg and abroad", commented Gregory Pels, head of payroll at SD Worx Luxembourg.

Microtis, which presents itself as the leader of the HR market in Luxembourg and counts the Red Cross, Chaux de Contern, Dussmann, Losch and LuxAirport among its clients, has developed Gesper Time Management, which even includes a virtual time clock in MyGesper.

According to, there are 36 technologies available to do the same job of recording the working time of its employees.

The latest? Ekronoz, recently launched by Kevin Trebossen to invite companies to switch to digital timekeeping.

It remains to be seen how tax authorities will give credit or not to these technological players. "The classic proofs that we recommend to our employees are purchase invoices, validated transport tickets, restaurant bills or other documents, but all this remains at the discretion of the controller," says Pascal Robert, CEO of Microtis.

This story was first published in French on . It has been translated and edited for Delano.