Is it illegal to do the odd job on the side?
- KVK Editors
- Background
- Edited 30 March 2026
- 1 min
- Rules and laws
Do you make a bit of extra money in the hospitality business, or as a cleaner? Or do you sell home-made cakes, for example, or jewelry? You have to report these extra earnings to the Belastingdienst. If you do not, you are working 'under the table', and you risk a fine.
Urban myth about zwartwerken
Doing paid work without reporting it to the Tax Administration is called zwartwerken in Dutch. And, just as in other countries, it is illegal. The idea that you are allowed to earn extra income up to a certain amount is not true. You may work as much as you want, but you have to report your to the Netherlands Tax Administration (Belastingdienst ). How much tax you have to pay on the extra earnings depends on your personal situation and other income. If you receive a benefit, the amount you earn may affect it. If your income is  (in Dutch), the tax levied on the extra income will be low or none.Â
Making extra money and paying taxes
You report the extra money you make as inkomsten uit overig werk (income from other activities, in Dutch) in your income tax return. If you have made expenses to earn the extra income, such as travel costs, you may deduct them from this amount.Â
If you do not report the extra income you make, and the Tax Administration finds out about it, not only will you have to pay the tax, but you also receive a  (in Dutch).
Risks of undeclared work
Undeclared work is not without risks. As an undeclared worker, you are not insured. For example, if you have an accident or cause damage. Nor do you build up any rights to benefits. You do not accrue holiday pay, year-end bonus, or pension and you are not protected against dismissal.
If you are receiving benefits, such as unemployment benefit or social assistance, and the Netherlands Tax Administration catches you working illegally, you could face problems. This applies even if you are applying for benefits.
Money on the side and registration with KVK
If you only make some extra money occasionally, you do not have to register as a business with KVK. Are you not sure? Contact the KVK Advice Team.


