Belgium has established a set of regulations to ensure that the rights of workers are respected. Foreign employers must comply with national legislation regarding the posting of workers in Belgium. Among these obligations, the LIMOSA form and the Check-In At Work system play an essential role. In this article, we will explore the main obligations related to posting of workers in Belgium, as well as the legal requirements involved.
What is the posting of workers?
Firstly, posting of workers occurs when a company from the EU temporarily sends employees to another EU country to carry out a specific service. For this to be considered a posting, there must be a working relationship between the company and the posted worker. Workers can only be posted if they already have an employment contract with the company. Moreover, the company posting the worker must carry out substantial and ongoing business in the home country.
Posted employees remain subject to the social security legislation of their home country, in line with European regulations. Article 12.1 of Regulation (EC) No. 883/04 specifically states that “[…] provided the expected duration of the work does not exceed 24 months and the person is not replacing someone else.” In accordance with this regulation, workers posted to another EU country may remain affiliated with their home country’s social security system for the entire duration of the posting (which is limited to 24 months). However, this 24-month limit (from a tax perspective) may be reduced depending on the double taxation treaties concluded between Belgium and the other country. For example, check our article about double taxation treaty between Belgium and Spain.
Non-EU workers
In addition, Regulation (EU) No 1231/2010 extends the application of the rules on the posting of workers and of Regulation (EC) No 883/2004 to third-country nationals who, due to their nationality, would otherwise not be covered. However, even if they are third-country nationals (from outside the European Union), they must be legally working in an EU Member State on the basis of a valid residence or work permit. This regulation does not apply to the United Kingdom or Denmark.
It should also be noted that on 9 August 1994, the Court of Justice of the European Union (CJEU) delivered its judgment in Raymond Vander Elst v Office des migrations internationales (Case C-43/93). The Court established that foreign workers are entitled to freedom of movement under the same conditions as EU citizens, provided that they legally reside and work in an EU Member State.
Procedures for posting of workers to Belgium
The posting of workers to Belgium requires compliance with a series of administrative formalities before and during the provision of services, in order to meet Belgian and European regulations. Failure to comply may result in significant penalties, both financial and administrative, as we will explain later. Below are the main requirements:
A1 form
For a temporary posting within the EU/EEA/Switzerland, the A1 form must be obtained by the employer (or by the self-employed person) by submitting an application to the competent Social Security authority in the country where the worker is insured (the “home country”). That authority assesses whether the conditions for the posting are met and, if so, issues the A1 certificate. This document confirms that, for the period indicated, the worker remains subject to the Social Security legislation of the home country and is not required to pay contributions in the host country.
‼️ Important: The A1 form must be requested and obtained before the worker is officially posted.
LIMOSA form
The LIMOSA form is a mandatory declaration for any foreign employer posting staff to Belgium, including employees, self-employed workers, and trainees. This procedure allows the Belgian authorities to monitor and register cross-border work activities, ensuring equal conditions between local and foreign companies. The employer must submit the LIMOSA declaration before the start of the activity and keep proof of submission for the entire duration of the posting. The declaration includes details of the employer, the worker, the Belgian client, and the duration of the services.
💡 Practical tip: Many labour inspections in Belgium begin precisely by checking this declaration. For this reason, it is strongly recommended to complete it in advance and keep a printed copy at the workplace.
How to obtain the LIMOSA form in Belgium?
The LIMOSA declaration is submitted through the official Belgian portal (limosa.be) and must be filed before the activity in Belgium begins. Once the procedure is completed, the Limosa-1 certificate is issued. This document must be given to the worker and kept (ideally also in printed form or readily accessible on site) throughout the entire posting period. You can find detailed information in our article on LIMOSA in Belgium.
Check-In at work
Check-In At Work is a legal requirement for certain industries, such as construction, real estate work, or the food sector. This system allows the presence of posted workers on-site to be tracked. For instance, it helps verify workers’ attendance on a construction site, facilitating social security checks and ensuring compliance with working conditions.
‼️ Failure to comply with the Check-In At Work registration requirement can result in fines and severe penalties, which is why it is essential to complete all steps correctly.
Liaison person of the company
In addition, when posting workers to Belgium, a local representative must be appointed to act as a point of contact with the authorities. This representative must be able to provide documents related to the posting, such as employment contracts, payslips, proof of social security contributions, and certificates. These documents must be available for inspection by the Belgian authorities.
Any foreign employer posting workers to Belgium is required to designate a contact person or local representative. This representative acts as an intermediary, facilitating communication between the employer and the workplace, as well as during labour inspections. Their main responsibilities include providing documentation related to the posting, responding to requests from the social inspection services in the event of checks, and assisting with the monitoring of working conditions and workers.
💡 Important: Inspections and verification of working conditions should never be obstructed. It is recommended to appoint a trusted representative or a supervisor of the workers.
Procedure for posting of workers to Belgium | Step-by-step guide
| Step | Action required | Details | Responsible party | Relevant authority |
|---|---|---|---|---|
| 1 | Verify eligibility of posting | Ensure the worker is legally employed in the sending country, and the posting is temporary and justified. | Employer in sending country | EU Directive (96/71/EC) |
| 2 | Double taxation agreement (DTA) | Determine if there’s a tax treaty between the sending country and Belgium to avoid double taxation. | Employer | OECD Tax Treaties |
| 3 | Assess income tax obligations in Belgium | Determine if the worker becomes Belgian tax resident or liable for tax (typically after 183 days). | Employer / posted worker | Belgian FPS Finance |
| 4 | Prepare a valid posting agreement | Include essential terms: host company, tasks, salary, duration, and social security coverage. | Employer in sending country | Lawyer |
| 5 | Appoint a liaison representative in Belgium | A required point of contact during inspections. Must reside or be contactable in Belgium. | Employer in sending country | Belgian Social Inspectorate |
| 6 | Submit Limosa declaration | Notify the Belgian authorities before the work begins. Print and retain confirmation. | Employer / representative | Limosa |
| 7 | Obtain the A1 Certificate | Confirms continued social security coverage in the home country. | Social security body of sending country | National institution (e.g., INSS, URSSAF, etc.) |
| 8 | Ensure compliance with Belgian labour conditions | Guarantee the posted worker’s core rights: minimum wage, working time, holidays, health & safety. | Employer in sending country | Belgian Labour Inspectorate |
| 9 | Prepare required documents for inspection | Employment contract, payslips, timesheets, proof of wage payment, Limosa receipt, A1 certificate, etc. | Employer / representative | Belgian Social Inspectorate |
| 10 | Respect duration limits | Respect duration of the EU and national legislation | Employer in sending country | Labour Inspectorate |
| 11 | Declare end of posting & check exit tax compliance | Notify Belgian authorities of end of posting and resolve any final tax/social issues. | Employer | Limosa Portal, FPS Finance, local social authorities |
Upon arrival of workers in Belgium
When the worker’s stay and posting exceed three months, the registration and residence obligations required under Belgian and European legislation must be fulfilled, both for EU citizens and for non-EU (third-country) workers.
Municipal registration and E card for European Union citizens
When the posted worker is a citizen of a European Union Member State, a registration certificate must be requested from the municipality where the worker will reside. After verification of the residence, the municipality issues the E card, which certifies the worker’s right of residence in Belgium for professional reasons. To obtain it, the worker must provide documentation proving the employment relationship, such as an employment contract. This registration does not replace other prior formalities, such as the LIMOSA declaration or the designation of a local contact person, but rather complements them within the overall legal compliance framework.
Residence permit and D visa for non-EU workers
Posted workers who are third-country nationals (outside the EU) must obtain a residence permit before starting their professional activity in Belgium. In general, the procedure begins in the country of origin by applying for a type D visa at the Belgian embassy or consulate. Once in Belgium, the worker must register with the municipality of their place of residence, where their address will be verified and a residence permit (A card) will be issued. This document authorises the worker to remain in Belgium for the duration of the posting. In certain cases, if the worker already legally resides in Belgium, the application may be submitted directly to the local authorities.
The EU Blue Card in Belgium
The European Union Blue Card (EU Blue Card) is a long-term residence and work permit intended for highly qualified workers from non-EU countries. In Belgium, this permit offers more favourable conditions than the traditional D visa and allows professional mobility within the EU, as well as the right of residence. To obtain a Blue Card in Belgium, the applicant must meet the following requirements:
- Hold an employment contract of at least 6 months with a Belgian employer
- Demonstrate professional qualifications, usually through a degree or equivalent experience
- Earn an annual gross salary above the minimum threshold set by the Belgian authorities (updated annually)
- Have no criminal record
When is it advisable to apply for it?
The Blue Card is recommended when the worker expects to remain in Belgium for at least 6 months, performs a qualified role within the company, wishes to move within other EU countries, and seeks a more stable residence status than a temporary visa. In addition, the EU Blue Card offers advantages for family reunification.
💡Practical tip: For both EU citizens and non-EU workers, it is advisable to plan residence formalities well in advance.
Documentation to be kept during the posting
During the posting of workers to Belgium, companies must have documentation available that allows the authorities to verify compliance with legal obligations. This documentation must be up to date and easily accessible. The documents that must be kept and, where applicable, presented during an inspection include:
- A copy of the employment contract or the posting/assignment letter
- Records of working hours, including rest periods and overtime
- The A1 form issued by the social security institution of the home country, certifying the worker’s social security coverage during the posting
- Documentation relating to working conditions
These documents must be retained for the entire duration of the posting in accordance with Directive (EU) 2014/67 on the posting of workers. The local representative appointed in Belgium is responsible for providing this documentation if requested by the inspection authorities. The documentation also constitutes a legal safeguard in the event of a labour or tax dispute.
Social protection and labour rights in Belgium
Workers posted to Belgium enjoy social and labour protection equivalent to that of local employees, in accordance with the requirements of Belgian law and European Union law. This guarantee is primarily based on Directive 96/71/EC, which reinforces the principle of equal treatment between local and posted workers. Under this framework, companies posting workers to Belgium must ensure compliance with the working conditions applicable in the host country, such as working time, rest periods, paid annual leave, and occupational health and safety.
In addition, posted workers must receive at least the applicable minimum wage in accordance with the relevant Belgian sectoral collective bargaining agreement, including any mandatory supplements and bonuses. At the same time, during the assignment, employees remain affiliated with the social security system of their home country, provided they hold a valid A1 form, in accordance with Regulation (EC) No 883/2004, thereby avoiding double social security contributions. With regard to workplace safety, the employer must ensure a working environment that complies with Belgian rules on risk prevention, safety training, hazard assessment, and the provision of personal protective equipment (PPE).
Tax implications for posting of workers to Belgium
Besides, it is essential to determine which country is responsible for taxing the salary when posting of workers in Belgium. As a rule, employees are taxed in the country where they work. However, in the case of a temporary assignment, the worker can continue to be taxed in their home country during the posting, under certain conditions. To determine which state, either the residence country or the host country, is responsible for taxing the income earned during the assignment, three criteria must be examined in Belgium:
- The total duration of the temporary stays in the host country must not exceed 183 days during the calendar year.
- The worker’s salary must be paid by an employer who is not based in the country where the worker is posted.
- The cost of the salary must not be borne by a permanent establishment located in the country where the worker is posted.
Consequently, it is important to note that these three conditions must be met cumulatively for the home country to retain tax jurisdiction. If one of the conditions is not fulfilled, the worker will be taxed in the country where they carry out their activities. Thus, if workers spend more than 183 days in Belgium, they will be required to pay income tax there.
Penalties for non-compliance in the context of postings
Compliance with the obligations related to the posting of workers to Belgium is strictly monitored by the authorities, such as the Federal Public Service for Employment (FPS Employment) and the National Social Security Office (NSSO). These bodies carry out frequent inspections to verify that foreign companies comply with legal requirements, including the LIMOSA declaration, registration in the Check-In at Work system, the appointment of a local contact person, and compliance with Belgian working conditions.
In the event of non-compliance, penalties may be administrative or criminal, depending on the seriousness of the infringement. Administrative fines may reach up to 18.000 EUR per worker, in accordance with the applicable legislation. The most severe sanctions are imposed where serious irregularities are identified, such as undeclared work, falsification of documents, or the absence of a genuine employment relationship between the home company and the posted worker. In addition, the Belgian authorities may order the immediate suspension of activities or even temporarily prohibit the provision of services on Belgian territory in cases of repeated non-compliance. For this reason, it is essential that companies verify all formalities in advance and properly document each posting, ideally with the assistance of a legal adviser specialised in Belgian and European labour law.
Sectors with more risks| Construction, engineering, transport and food industry
The posting of workers to Belgium is subject to enhanced controls in certain sectors. These include construction, international road transport, and the food industry, where the high number of posted workers and extensive subcontracting require closer supervision. In the construction sector, the Check-In at Work system is mandatory for all workers present on a construction site, both Belgian and foreign. This electronic registration system makes it possible to verify the presence and legal status of each worker in real time. Companies must also comply with the sector’s collective bargaining agreements, which set out rules on wages, safety, and working time. In road transport, Belgium strictly enforces European rules on driving and rest periods, as well as the provisions of the EU Mobility Package. Roadside inspections are carried out jointly by the federal police and the regional transport authorities.
The food industry and the hospitality sector, for their part, are characterised by high staff turnover and temporary employment, which leads to more frequent checks on compliance with minimum wage rules, food safety standards, and the regularity of employment arrangements. Overall, these sectors account for the majority of inspections and detected infringements. As a result, proper legal compliance and up-to-date documentation are key to avoiding fines and administrative suspensions.
Practical recommendations for companies posting staff to Belgium
Before carrying out a posting of workers to Belgium, companies should undertake careful planning in order to comply with the Belgian and European regulatory framework. As part of this planning, the employer must correctly complete the LIMOSA declaration, appoint a local representative in Belgium, and prepare a complete documentation file, including employment contracts, payslips, A1 forms, and other relevant documents.
In addition, it must be verified that posted staff receive at least the applicable Belgian sectoral minimum wage in accordance with the relevant legislation and collective bargaining agreements. It is also advisable to translate the documentation into the language of the destination region (French, Dutch, or German) in order to facilitate social inspections. Another recommended practice is to establish a compliance protocol that allocates responsibilities among the relevant departments (such as human resources or finance) involved in the posting. This helps ensure proper document control and updating, as well as effective coordination with the appointed representative in Belgium.
Summary table | documentation, implementation, and risks
| Area | Practical recommendation | What to implement | Evidence | Risks |
|---|---|---|---|---|
| Scope of the posting | Confirm whether it qualifies as a “posting” or a business trip | Define internal criteria (duration, provision of services, client/worksite, subordination) and document the decision | Documented internal criteria | Incomplete or incorrect procedures, fines, inspection issues |
| Planning | Create a country-specific file (Belgium) | Project-based documentation: social security, LIMOSA, sector, worksite, working hours, documentation, tax aspects | Approved and signed by the assigned responsible person | Delays, non-compliance |
| Social security | Manage the A1 certificate well in advance | Application, follow-up, and verification of duration | A1 per worker | Avoid double contributions, inspections, and regularisations |
| LIMOSA | Submit the declaration before the start of work and provide the certificate | Assign responsibility and validate worker data | Limosa-1 per worker | Fines, suspension of activities, liability |
| Check-In at Work | Verify applicability by sector/worksite and comply with registration | Check subcontractors and control entry/exit | Registration records | Specific penalties in regulated worksites/sectors |
| Documentation | Prepare a file per worker and per project | Folder including: ID, contract/assignment, A1, LIMOSA, working time records, payslips, etc. | Complete dossier per worker/project | Fines and sanctions during inspections |
| Working conditions | Validate minimum Belgian wages and conditions | Review collective agreements, sectoral conditions, and comparison with home-country terms | Labour compliance report | Wage claims, sanctions, and litigation |
| Working time | Ensure traceability of working hours and rest periods | Time-recording system | Working time records | Labour law breaches and penalties |
| Subcontracting | Control the chain (client and subcontractors) | Contractual clauses and prior document verification | Contracts and documentary checks | Joint and several liability |
| Taxation | Assess the risk of taxation in Belgium (e.g. 183-day rule) | Residence criteria and tax coordination | Documented tax report/criteria | Incorrect withholdings and penalties |
| Immigration (non-EU) | Treat as a specific case (do not mix with EU postings) | Determine worker status, permits, and exemptions | Permits | Refusals, fines, work bans |
| Health and safety | Adapt safety measures to Belgian rules and the assignment | Coordination of activities, training, equipment | Risk assessments | Accidents, work stoppages, civil and criminal liability |
| Language and communications | Ensure documentation is available in the local language | Documents in FR/NL/DE depending on the region | Translated documentation package | Delays, misunderstandings, poorer inspection outcomes |
| Evidence and archiving | Retain evidence during and after the posting | Record retention policy | Retention policy | Inability to demonstrate compliance |
Do you need assistance with the posting of workers to Belgium?
Properly complying with all obligations related to the posting of workers to Belgium—including the LIMOSA form, Check-In at Work, the E card, the D visa, or the EU Blue Card—can be challenging without appropriate guidance. At Arthur & Marin, our lawyers specialised in European law, Labour law, Corporate law, and International Law matters advise you at every stage. From the initial planning of the posting, to obtaining residence permits in Belgium and the required documentation, as well as follow-up and defence in the event of inspections or sanctions.
Contact us today at info@arthurmarin.com or call us on +32 465 345 345 to receive personalised legal advice and ensure that your company fully complies with Belgian and European legislation.
Ensure the success of your work postings to Belgium with the support of experienced professionals. Fast. Compliant. Reliable. Let’s make your cross-border workforce a success.
FAQ | Posted workers in Belgium
1) What is the posting of workers to Belgium?
It refers to a situation in which a company established in another country temporarily sends staff to Belgium to provide a service. The employment relationship is normally maintained, Belgian law applies, and certain working conditions of the host country must be respected.
2) What are the basic formalities usually required to post staff to Belgium?
In practice, the minimum package usually includes: the A1 certificate (social security of the home country), LIMOSA (the Belgian declaration), and, where applicable, Check-In at Work (presence registration) in specific sectors.
3) Who applies for the A1 form and where is it obtained?
The employer (or the self-employed person) applies to the Social Security institution of the country where the person is insured (the “home country”). The A1 certifies which social security legislation applies during temporary work in another country.
4) How long is the A1 valid and can it be extended?
In the context of postings, the A1 covers up to 2 years (24 months).
5) What is LIMOSA and when must it be submitted?
LIMOSA is the mandatory Belgian declaration for the temporary activities of posted workers. Proof of submission (Limosa-1) must be obtained before starting work in Belgium.
6) What is the Limosa-1 certificate and what is it used for?
Once the declaration is completed, the system generates a receipt (Limosa-1). This document must be provided or shown to the Belgian client before work starts and often includes a QR code that is useful for Check-In at Work in the construction sector.
7) What happens if I do not submit Limosa-1 (or cannot prove LIMOSA)?
If you are unable to present proof of Limosa-1, the Belgian client or contracting party is obliged to notify the Belgian authorities (with very limited exceptions).
8) Does LIMOSA replace the A1?
No. LIMOSA is a Belgian administrative formality. The A1 certifies the applicable social security system (home country) in an intra-EU/EEA/Switzerland posting. They are complementary.
9) When is Check-In at Work mandatory in Belgium?
It is mandatory for certain types of work, sectors, or contracts (above a certain financial threshold), and it also applies to specific activities in the meat sector carried out in facilities subject to authorisation or registration.
10) Who is responsible for registering presence in Check-In at Work?
Responsibility lies both with the party sending the workers (or the Belgian client at the workplace) and with the party performing the work. There should be an operational agreement on who carries out the registration, and both parties must verify that it has been completed.
11) How can Check-In at Work be registered if I am a foreign company (without Belgian infrastructure)?
There are several methods. A practical option is to register by scanning the QR code on the Limosa-1 (L1).
12) Can a LIMOSA declaration be extended or amended if the assignment is prolonged?
Yes, it is possible to extend the declaration if the duration exceeds what was initially declared (with specific rules regarding workplaces). It is recommended to review and update it before the declared period expires.
13) Which documents should be readily available in the event of an inspection?
At a minimum, immediate availability of the A1, the employment contract, the Limosa-1, and, where applicable, proof of Check-In at Work registration. It is good practice to keep a dossier per worker including the assignment letter, working time records, and evidence of compliance.
