Must an employee also be able to report orally?

Oral reporting must be possible in addition to written reporting

Yes, an employee must also be able to make a report orally; a reporting channel that only offers a written form does not comply. The directive on which the national laws are based requires that an internal reporting channel makes both written and oral reporting possible. Oral reporting can be via a telephone line or another voice system, and at the request of the reporter also via a face-to-face conversation. It is therefore not up to the employer to determine that only text is accepted; the choice of how someone reports is up to the reporter themselves.

In practice, this means that an organisation must offer a way to record or discuss something in addition to a written reporting page, and that the voice recording or conversation is documented and handled with the same care as a written report. An employee who prefers not to type, or who wants to clarify something that is difficult to capture on paper, must therefore have that option. This also applies if someone prefers not to give their name: the form of reporting (written, oral or in conversation) is separate from the question of whether someone does so anonymously.

Where this is laid down: Article 9 directive and Article 2 WBK

This requirement comes directly from Article 9 of Directive (EU) 2019/1937, which requires that internal reporting channels must allow both written and oral reporting. The Dutch Whistleblower Protection Act implements this directive in the requirements for the internal reporting procedure, regulated in Article 2 of that act. For the precise wording and the exceptions mentioned by the directive and the act itself, the statutory text is the appropriate source.