Ancillary activities: what can an employer prohibit or restrict?

Your employer may only prohibit or restrict work you do for others outside your working hours if there is an objective reason for it. Under Article 7:653a of the Dutch Civil Code (BW), in force since 1 August 2022, a clause without such a justification is void; the main exception is a concrete risk such as a breach of the Working Hours Act (Arbeidstijdenwet), a conflict of interest or the protection of confidential information.

This applies to a side job, your own business, freelance assignments and board positions alike. In Dutch tulafono o galuega these are called ancillary activities (nevenwerkzaamheden), and the clause that regulates them is the ancillary activities clause (nevenwerkzaamhedenbeding).

What does Article 7:653a BW say?

A clause that prohibits or restricts work for others outside your working hours is void, unless it can be justified on an objective ground. The rule implements Article 9 of Faatonuga (EU) 2019/1152 on transparent and predictable working conditions.

A written clause is therefore not automatically valid, nor automatically invalid. What counts is whether the employer can point to an objective justification at the moment it relies on the clause. Article 7:653a(2) BW adds that the employer may not treat you less favourably because you invoke these rights, in or out of court.

The subdistrict court (kantonrechter) of The Hague applied this test in a case where an employee took a second job of up to 16 hours a week alongside her full-time position without the required permission, while on sick leave. The court accepted the risk of exceeding the Working Hours Act as an objective reason and weighed the employee’s interests against it; the summary dismissal was upheld (ECLI:NL:RBDHA:2024:21917).

Does a consent requirement also fall under the rule?

Yes. A clause requiring prior consent restricts your freedom in the same way as a ban, so the employer may only refuse consent for an objective reason.

The Arnhem-Leeuwarden Court of Appeal confirmed this on 15 June 2026: a permission clause falls within the scope of Article 7:653a BW, and the employer “may only refuse consent if there is an objective reason” (ECLI:NL:GHARL:2026:3919). A refusal at the employer’s discretion is therefore not enough.

How does a notification duty differ from a consent requirement?

Under a notification duty you only report the activity; the employer then assesses whether there is reason to act. Under a consent requirement you need approval before you start. Neither may be used as a disguised outright ban, and both are tested against Article 7:653a BW once the employer uses them to restrict you.

O a ni mafuaaga faapitoa e mafai ona tauamiotonuina ai se tapulaa?

The law gives no exhaustive list. Article 9 of Directive (EU) 2019/1152 names health and safety, business confidentiality, the integrity of the public service and the avoidance of conflicts of interest as examples. In Dutch case law the following grounds recur:

• the risk that combined working hours breach the Working Hours Act and its rest periods;
• protection of trade secrets and competitively sensitive information;
• a conflict of interest, for example work for a direct competitor;
• safety risks from fatigue, especially in safety-sensitive positions;
• the integrity or independence of the position, for example in government or supervisory roles.

A general reference to “business interests” is not enough. The subdistrict court of Midden-Nederland held a clause void on 23 October 2024 because the employer had not explained what concrete risk arose for this employee and this activity; its claim for a €10,000 penalty was dismissed (ECLI:NL:RBMNE:2024:6411).

Must the reason be written in the clause itself?

No. Article 7:653a BW only requires that the justification exists when the employer relies on the clause, for example when it refuses consent. Naming the interest in the clause from the start does prevent disputes and makes a later refusal easier to substantiate.

How does an ancillary activities clause differ from a non-compete clause?

A fuaiupu le tauva under Article 7:653 BW restricts you after the employment ends; an ancillary activities clause restricts you during the employment. The two are tested differently.

A non-compete clause is only valid if it was agreed in writing with an adult employee, and in a fixed-term contract only with a written statement of the employer’s weighty business interests (Article 7:653(1) and (2) BW). A restriction on competing work while you are still employed is not a non-compete clause but an ancillary activities clause, so Article 7:653a BW applies. Contracts and staff handbooks regularly mix the two up, which leads to disputes about which test applies.

What are your rights and obligations as an employee?

In principle you decide for yourself whether and for whom you work outside your working hours. In return, you must comply with a valid notification duty or consent requirement and give accurate information about the nature, hours and client of the activity.

Your general duty to act as a good employee (Article 7:611 BW) continues to apply, even if the clause turns out to be void. You may not use your employer’s confidential information or facilities for your side activity. If you believe consent was wrongly refused, you can ask the subdistrict court to rule on it.

Can the employer take your hours elsewhere into account?

Yes. For the Working Hours Act, the hours you work for another employer or as a self-employed person count towards your total working time and rest periods.

An employer that sees the maximum working hours or minimum rest periods being exceeded therefore has a recognised objective reason to restrict the activity. Fatigue in a safety-sensitive role, such as transport or care, can also justify a restriction.

Does it matter whether your contract is fixed-term or permanent?

No. Article 7:653a BW makes no distinction between konekarate tumau and permanent contracts, and it also protects temporary agency workers and on-call workers.

The nature and duration of the position can play a role in whether a justification exists, for example a short project with access to highly confidential information. The test itself stays the same: the employer needs a concrete, individual reason.

O le ā e tatau ona e siakiina pe afai o oe o se pule o galuega?

• Is the clause a notification duty, a consent requirement or a ban, and is that stated explicitly?
• Is each restriction linked to a concrete interest, such as confidentiality, safety or the Working Hours Act?
• Is the clause clearly separated from the post-employment non-compete clause of Article 7:653 BW?
• Do you assess each consent request individually and record a refusal in writing with reasons?
• Do you monitor the employee’s total working time and rest periods?
• Have existing contracts and the staff handbook been reviewed against Article 7:653a BW since 1 August 2022?

O a mea e tatau ona e siakiina pe afai o oe o se tagata faigaluega?

• Does your contract or staff handbook contain a ban, a consent requirement or only a notification duty?
• Have you reported the side activity in time, with its nature, hours and client?
• Does the activity overlap with your employer’s customers or market?
• Do your combined hours stay within the Working Hours Act limits?
• If consent was refused: did the employer give a concrete reason in writing?
• Have you taken advice before ignoring a ban or refusal? Breaching a valid clause can lead to a penalty or dismissal.

What can we do for you with ancillary activities?

O lo tatou loia faigaluega advise both employers and employees on ancillary activities clauses.

• We review your ancillary activities clause and staff handbook against Article 7:653a BW.
• We draft a clause or policy that names the protected interest and a clear consent procedure.
• We assess whether a refusal of consent is supported by an objective reason.
• We draft the letter asking your employer for the written reasons for a refusal.
• We conduct proceedings before the subdistrict court about a refusal, penalty or dismissal.

aotelega

• Since 1 August 2022, a clause restricting work outside working hours is void without an objective reason (Article 7:653a BW).
• A consent requirement falls under the same test; the employer may not refuse at its discretion.
• Recognised reasons include the Working Hours Act, confidentiality, conflicts of interest and safety.
• The justification must be concrete for this employee and this activity.
• An ancillary activities clause applies during employment; a non-compete clause (Article 7:653 BW) after it.

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