Guide to Belgian and Dutch companies operating across the border

Working across borders: Belgium - Netherlands

Administrative notifications and permits

Companies must comply with separate notification requirements in each country when working across borders. For a Belgian company sending employees to the Netherlands (or vice versa), the WagwEU notification applies. (Wet arbeidsvoorwaarden gedetede werknemers EU). This means that the foreign employer must report the deployment in advance must report the deployment in advance via the online Postedworkers notification desk of the Dutch Labor Inspectorate. Self-employed workers may also be required to report. If the foreign employer and the Dutch client may be subject to fines (max. approx. €4,500).

A Dutch company that employs employees in Belgium is subject to the mandatory Limosa-1 notification. Each foreign employee hired must be digitally notified before commencement to the Belgian government before the start. Upon request, the employee or client must be able to show the Limosa certificate (L1 form) upon request. Again, both employer and principal risk criminal or administrative penalties in the absence of the notification. In addition, since 2016, the Belgian posting law requires that the foreign employer must designate a local liaison person in Belgium.

Finally, cross-border employment almost always requires an A1 attestation (Certificate of Coverage) is needed to arrange social security. The A1 form proves that the worker is covered by the home country's social security system during the assignment. Without A1, the employee may not even be allowed to work in some countries. The employer (or the employee) applies for the A1 to its own social security agency (RSZ/RSVZ in Belgium or SVB in the Netherlands) before the work start in the neighboring country.

Hour registration, mileage reimbursement and GPS

Hour registration:The Netherlands has a strict obligation: every employer must keep track of the hours worked (and breaks) so that the Labor Inspectorate can check compliance with the Working Hours Act. In Belgium, for a long time there was no general obligation to record hours. Since 1 July 2024. there has been an obligation in the case of flexible working hours - companies are then obliged to use a recording system (e.g. time clock or app. (e.g. time clock or app), otherwise they risk penalties. For fixed schedules, it is not yet mandatory, although registration is often desired for planning and wage calculations.

Kilometer allowance: In both countries, employers are allowed to give an untaxed flat-rate allowance per km give, but the maximum amounts differ. In the Netherlands, the tax-free allowance for 2024 is set at €0.23 per km. In Belgium, it is much higher (depending on quarterly or annual indexing, approximately €0.43-0.44 per km in 2024). Allowances above these maximums are considered wages in both countries and taxed. In Belgium, in addition, quarterly indexing has applied since 2022 to track fuel fluctuations.

GPS location: The use of GPS to track mobile workers is permitted in both the Netherlands and Belgium, but only under strict privacy conditions (AVG). The Dutch Personal Data Authority emphasizes that the employer must have a justified interest and must weigh employee privacy against business interests. Tracking may not take place 24/7; employees must be able to turn off GPS in private situations. In Belgium, the same rules apply, supplemented by guidelines from the Data Protection Authority: purpose, proportionality and transparency are required. Thus, long-term 24-hour tracking is prohibited and the system must be included in the labor regulations. In practice, it is essential to clearly inform employees about what is being recorded and why.

Social security, taxes and posting

Detachment: Employees generally remain insured in the employer's home country. The A1 certificate allows the employee to work in the other country for up to 2 years without paying new social contributions having to pay new social contributions in the host country. Similar arrangements exist for the self-employed through RSVZ/RSZ. In the EU/EEA, posting is allowed up to a maximum of 24 months (with extension up to 3 years possible). Afterwards, the host country can levy social contributions if the work lasts longer.

Taxes: Here national rules and treaties apply. A common rule is the 183-day rule: if the employee does not spend more than 183 days in the host country within 12 months, normally the home country continues to tax. The Tax Office of the Netherlands states: "May the country to which you have been posted levy tax? Then your employer does not have to withhold Dutch to withhold Dutch wage tax. If the Netherlands is allowed to levy tax, your employer must withhold wage tax and contributions in the Netherlands." In practice, cross-border assignments often involve prior coordination of which wage tax is applicable. In certain cases, special regimes apply, such as the 30% rule for expats in the Netherlands. In Belgium, foreign employees basically pay Belgian payroll tax when they work there, but under the 183-day criterion, they often continue to file returns in their home country, possibly with offsetting.

Documents required for audit and penalties

In both the Netherlands and Belgium, an employer must be able to show all documents that support a posting. In Dutch workplaces, the following must be present during inspection, among other things: employment contracts, pay slips, timesheets, the A1 form and proof of wage payments. These records must be kept for at least five years. It must also be clear which company one works for in the Netherlands (contact person with client). During Belgian inspections, a company must prove that the Limosa declaration has been made (L1 proof), that the A1 is present, and that Belgian working conditions are met (pay slips, health and safety documents, etc.).

Fines: Exceeding the rules leads to high penalties. In the Netherlands, failure to report posting or reporting it incorrectly can result in a fine of up to about €4,500. Clients also risk fines if they do not check whether the report has been made. In Belgium, ignoring the Limosa obligation can result in criminal and administrative penalties. Both employer and Belgian principal can be held responsible. The A1 form plays a central role here: without A1, the employee's social security is not proven, which creates additional risk during inspections.

Digital tools: Done-it app

Modern software can greatly facilitate compliance with these rules. One example is the Done-it-app, developed especially for companies with mobile employees. With Done-it, an employee records their start and end times digitally (clocking in and out) via GPS-integrated location tracking. Thus, the system automatically links the hours worked to the physical work address, which helps with mandatory timekeeping.

The app also lets employees record trips: for each trip, they enter the miles driven, the means of transportation and any carpool information. This creates a conclusive overview of all business kilometers for correct mileage reimbursements. Overtime can be tracked via the app and automatically converted into extra time off or extra pay.

In addition, Done-it provides a central place to share project documents and updates with staff (for example, site instructions or safety rules). Through these digital resources, a company always has real-time visibility into hours, travel and locations. During an inspection, the necessary data - clock-in and clock-out times, work addresses and trip records - are readily available. Such an integrated system supports compliance with both Dutch timekeeping requirements and Belgian guidelines, while also contributing to transparency towards employees (e.g. about GPS tracking).

In practice, this reduces manual paperwork and increases the likelihood that all administrative obligations are are met timely and correctly.