Unlike merchant ships, pleasure craft are allowed to sail at sea without a Certificate of Registry (Zeebrief). However, a Certificate of Registry issued in the Netherlands grants you the right to legitimately fly the Dutch flag and enjoy the rights that come with the Dutch nationality for your ship.
The Certificate of Registry is the official proof that a pleasure craft is registered in the Nederlandse vlagregister (Netherlands’ flag register, in Dutch). It confirms the vessel’s nationality and legal ownership. This helps to avoid problems in international waters.
Without a Certificate of Registry, the Dutch flag does not offer legal protection. The certainty and rights that come with a Certificate of Registry are not provided by other documents such as the International Certificate for Pleasure Craft (ICP).
Please be mindful that to be registered in the flag register as a pleasure craft, the seagoing vessel may not be used for commercial purposes in any way. If your vessel is registered as a pleasure craft, you are only allowed to use it for recreational purposes, or allow others to do so.
If you, on the other hand, intend to use the vessel for commercial purposes even occasionally, then you may not register it as a pleasure craft. In that case, the vessel must be registered as a merchant vessel. Please visit the general website for the registration of merchant vessels under the flag of the Netherlands here