Secondment agreement (detachering): what Dutch law requires

A secondment agreement (detacheringsovereenkomst) places an employee of one business at the disposal of another business, where he or she works under that other party’s supervision. The employment contract stays with the seconding employer, but Dutch law attaches consequences the parties cannot exclude by contract, such as the hirer’s pay rule and the hirer’s liability for unpaid wages.

Three mandatory consequences matter most. First, under Article 8 of the Placement of Personnel by Intermediaries Act (Wet allocatie arbeidskrachten door intermediairs, Waadi), the seconded worker is entitled to the same key terms of employment as comparable employees of the hirer, often under its collective labour agreement. Second, under Article 9a of the Waadi a clause that prevents the worker from joining the hirer after the assignment is void; only a reasonable fee for the introduction may be agreed. Third, under Article 7:616a of the Dutch Civil Code (BW), the hirer is liable towards the worker for the wages if the seconding party does not pay.

The rules are also changing. Under the Admission of Workers Act (Wet toelating terbeschikkingstelling van arbeidskrachten, Wtta), the admission system starts on 1 January 2027 and expressly covers secondment companies. Lenders that registered for the transitional arrangement between 1 November and 31 December 2026 apply for admission between 1 May and 30 June 2027. From 1 January 2028 lending without admission is prohibited, and the Netherlands Labour Authority can also fine hirers that use a lender without admission.

What does a secondment mean in practice?

An employee temporarily works for another organisation while remaining employed by the original employer. The secondment agreement between the two businesses records the terms.

The arrangement creates a three-way relationship. The seconding party (uitlener) holds the employment contract and pays salary, sick pay and benefits. The hirer (inlener) gives daily instructions and assigns tasks. The employee works for the hirer while remaining bound by his or her own employment contract. You see this model often in engineering, IT, construction and consultancy.

Some duties pass to the hirer by law. For working conditions, the hirer is treated as the employer under the Working Conditions Act (Arbeidsomstandighedenwet, Arbowet). Under Article 7:658 paragraph 4 BW, the hirer is liable in the same way as an employer if the secondee suffers damage in the course of the work, for example in a workplace accident.

How does a secondment differ from agency work and freelancing?

A secondee remains an employee of the seconding party; a freelancer is self-employed. An agency worker has an agency employment contract (uitzendovereenkomst, Article 7:690 BW), which often contains an agency clause under which the contract ends automatically when the assignment ends.

A secondee usually has an ordinary employment contract that continues after the assignment. The Waadi pay rule and the Wtta apply to both secondment and agency work. A freelancer (zzp’er) invoices for services and arranges his or her own taxes; since 1 January 2025 the Tax and Customs Administration (Belastingdienst) again enforces against false self-employment, which can lead to additional assessments for the hiring business.

Which Dutch rules apply to secondment?

The Waadi sets registration and pay rules, tax and wage chain liability put risks on the hirer, and for cross-border postings the rules on posted workers apply. From 2027 the Wtta admission system is added.

What are the Waadi registration and check obligations?

Under Article 7a of the Waadi, any business that makes workers available to another business for remuneration must be registered as a lender in the Commercial Register of the Chamber of Commerce (KVK). Before a seconded worker starts, the hirer must check that registration.

Skipping that check can lead to fines from the Netherlands Labour Authority (Nederlandse Arbeidsinspectie), calculated per worker. From 1 January 2027 most lenders also need Wtta admission, and hirers must then check that admission instead.

What is chain liability for taxes and wages?

The hirer can be held liable for payroll taxes and VAT that the seconding party does not pay, and for the wages of the secondee. You can limit that risk with a G-account and careful selection of the seconding party.

Under Article 34 of the Tax Collection Act 1990 (Invorderingswet 1990), the hirer is liable for the payroll taxes, and in some cases the VAT, that the seconding party owes for the work (inlenersaansprakelijkheid). Separately, under Article 7:616a BW the secondee can claim unpaid wages from the hirer, unless the hirer shows it is not to blame for the underpayment.

• G-account: pay the part of the fee that covers the estimated payroll taxes into the seconding party’s blocked account (G-rekening), which can limit your tax liability.
• Statement of payment history: regularly ask the seconding party for a verklaring betalingsgedrag from the Belastingdienst, which shows whether it pays its taxes on time.
• Contract protection: include a compliance warranty, audit rights and an indemnity in the agreement.

A worker from outside the EU, the EEA or Switzerland also needs a residence permit that allows the work, and often a work permit (tewerkstellingsvergunning, TWV) or a route such as the highly skilled migrant scheme or the intra-corporate transferee scheme. Working without the correct permit leads to fines for the business where the work is done.

What does the Posted Workers Directive mean for postings within the EU?

If an employer from another EU country posts an employee to the Netherlands, core Dutch terms of employment apply from day one. After 12 months, or 18 months after a reasoned notification, almost all mandatory Dutch employment rules apply.

The Posted Workers Directive (Directive 96/71/EC, as amended by Directive (EU) 2018/957) is implemented in the Terms of Employment of Posted Workers in the EU Act (Wet arbeidsvoorwaarden gedetacheerde werknemers in de Europese Unie, WagwEU). From day one, the posted worker is entitled to the remuneration under Dutch law and universally binding collective labour agreements, the Dutch rules on working hours and rest periods, the statutory minimum paid holidays and Arbowet standards. The foreign employer must notify the posting in advance through the Dutch notification portal, and the hirer must check that notification.

Since 30 July 2020, a posting longer than 12 months (or 18 months after a reasoned notification) brings almost all mandatory Dutch terms into play. The main exceptions are the rules on concluding and terminating the employment contract, non-competition clauses and supplementary pension schemes. Decide at the start whether a posting will cross that threshold, and allocate the extra costs in the agreement.

What should a secondment agreement contain?

Record the parties, duration, work, fee, intellectual property, confidentiality, liability, termination and applicable law. Anything you leave open will be argued about later.

The secondment agreement is concluded between the two businesses, so the employee is not automatically bound by it. Arrangements that affect the employee, such as a change of workplace or duties, must fit the employment contract, and the employee must usually agree to them. Many employers therefore also sign a short secondment letter with the employee.

Which core terms should you define?

Specify the full legal names, registered offices and KVK numbers of both businesses and the name of the employee. Add the exact start and end dates and any extension option, the address where the employee works, which matters for health and safety, travel costs and the applicable rules, and a description of the duties.

How do you arrange the fee and costs?

Set out the fee, how it is indexed and how it develops if the employee’s pay rises because of the hirer’s pay rule under Article 8 of the Waadi. Between businesses, the statutory payment term is 30 days if nothing is agreed (Article 6:119a BW). Also agree who pays travel, accommodation and equipment, and whether the fee continues or stops during illness or leave.

Who owns the intellectual property, and how do you protect confidential information?

By law, rights to works created by an employee usually go to the employer, which is the seconding party, not the hirer. If the hirer is to own the results, the agreement must provide for an assignment.

Under Article 7 of the Dutch Copyright Act (Auteurswet), the employer is in principle the author of works an employee makes in the course of the job. For inventions, Article 12 of the Dutch Patents Act 1995 (Rijksoctrooiwet 1995) gives the employer the right to the patent if the job involves making inventions. An assignment of copyright requires a written deed (Article 2 of the Copyright Act), so agree that the seconding employer assigns all rights to results created for the hirer.

Confidentiality clauses should protect the hirer’s information against disclosure, protect the seconding employer’s trade secrets against the hirer, and continue after the secondment. Bind the employee as well, through the employment contract or a separate statement, and agree how personal data is exchanged under the GDPR.

How do you arrange termination and liability?

Agree on notice periods, grounds for immediate termination and who bears which liability. Ending the secondment does not end the employment contract with the seconding employer.

If the secondee causes damage to a third party, both the seconding employer and the hirer may be liable under Article 6:170 BW, depending on who had control over the work. If the secondee is injured at work, the hirer is liable as an employer (Article 7:658 paragraph 4 BW). Often the hirer indemnifies the seconding employer against claims arising from work under its supervision. Check whether both parties’ liability insurance covers the arrangement.

Which clauses belong in every secondment agreement?

Use the table below as a final review before signing.

What are the risks of a secondment?

The main risks are confusion about who manages the employee, chain liability and an unclear employment relationship. A carefully drafted agreement, followed in practice, is your main protection.

The employee reports to the seconding employer on HR matters but takes daily instructions from the hirer. Record who conducts appraisals, approves holidays and handles disciplinary matters; usually the hirer supervises the daily work and the seconding employer handles formal appraisals and salary reviews.

The main legal risk is an unclear employment relationship. If the hirer in practice decides on pay, promotion and dismissal and the seconding party plays no real role, a court looks at the reality rather than the labels, and the employee may argue that the hirer is the actual employer. On top of that, the hirer carries the chain liability under Article 34 of the Tax Collection Act and Article 7:616a BW.

What should you check as the seconding employer?

You remain the employer throughout, so the employment duties stay with you.

• Check that you are registered as a lender with the KVK and have reported for Wtta admission.
• Check that the employment contract allows the secondment, or obtain the employee’s written consent.
• Apply the hirer’s pay rules under Article 8 Waadi and reflect them in your fee.
• Arrange continued pay of at least 70% of salary for up to two years during illness (Article 7:629 BW) and what happens to the fee.
• Plan the employee’s return role, because the employment continues after the assignment ends.

What should you check as the hirer?

You do not employ the secondee, but you carry part of the legal risk.

• Check the lender’s KVK registration before day one, and from 2027 its Wtta admission.
• Ask for a recent statement of payment history and agree a G-account.
• Give the seconded worker the same key terms as your own comparable employees.
• Provide safety instructions and a safe workplace, because you are liable under Article 7:658 paragraph 4 BW.
• For a posted worker from another EU country, check the WagwEU notification and the 12-month threshold.

What can we do for you with a secondment agreement?

As explained on our employment lawyer page, we advise seconding employers and hirers on secondment agreements, the Waadi and the Wtta.

• We draft or review the secondment agreement and the secondment letter for the employee.
• We check the Waadi pay rule and the applicable collective labour agreement for the hirer.
• We set up the compliance clauses: warranty, audit rights, G-account and indemnity.
• We advise on Wtta admission and the deadlines in 2026 and 2027.
• We assess postings from other EU countries against the WagwEU and the 12-month threshold.

Summary

• In a secondment, the employee remains employed by the seconding employer but works under the supervision of the hirer.
• The hirer’s pay rule (Article 8 Waadi), the ban on clauses that block a move to the hirer (Article 9a Waadi) and wage chain liability (Article 7:616a BW) apply regardless of what the parties agree.
• The seconding party must be registered under the Waadi; from 1 January 2027 the Wtta admission system applies, with a lending ban and fines for hirers from 1 January 2028.
• For postings from another EU country, core Dutch terms apply from day one and almost all mandatory terms after 12 (or 18) months.
• Arrange intellectual property, confidentiality, liability, illness and termination explicitly in the agreement.

Frequently asked questions