Netherlands voice guidelines

Voice calling guidelines for Netherlands (NL), covering reachability, caller ID formats, DTMF support, and emergency services.

Locale overview

Reachability

Netherlands supports inbound and outbound calls for domestic, international, and toll-free number types.

Outbound restrictions

The following outbound call behaviors are prohibited under the Dutch Telecommunications Act and applicable carrier policies:

• Scam, spam, and harassment — These calls are strictly prohibited under the Dutch Telecommunications Act.
• Nuisance, excessive, or aggressive calls — While not explicitly illegal, these calls may violate consumer rights if they disregard consumer preferences or cause undue disturbance.
• Cold calls (unsolicited telemarketing) — Unsolicited sales calls to individuals are prohibited unless the recipient has given prior explicit consent. An exception applies for calls to existing customers about similar products or services, provided there are clear opt-out options.
• Non-callable or fake caller line identification (CLI) — Misuse of CLI is prohibited, including spoofing, withholding, or using invalid or non-callable numbers, especially for telemarketing or unsolicited calls. Only valid, officially allocated (callable) numbers may be used as the CLI. Non-assigned or non-callable numbers (such as “one-way” CLIs) are not permitted.
• Non-standard CLI formats — Only valid, callable numbers in the correct format may be used. Non-standardized or improperly formatted CLIs are not allowed.
• Unlisted or inactive CLIs — Presenting an unlisted or inactive number as the CLI for outbound calls is prohibited.
• Flash calls — Flash calls are not explicitly banned by law, but regulatory controls around CLI validity and allocation may restrict them. Both the Authority for Consumers and Markets (ACM) and mobile network operators monitor and may block flash calls where they threaten the integrity of CLI presentation or user privacy.

Caller ID

DTMF support

DTMF is supported using RFC 2833 format for both inbound and outbound calls.

Emergency services

Calling emergency services is not supported.

Compliance note

These guidelines summarize carrier requirements at the time of publication and do not constitute legal counsel. Verify that your implementation complies with all applicable telecommunications regulations in Netherlands.