🇳🇱 Netherlands Phone Number Format
Dutch phone numbers are 10 digits in national format. All mobile numbers start with 06, while landlines use area codes starting with 0 — Amsterdam 020, Rotterdam 010, Den Haag 070. The trunk 0 is always dropped after +31: 06 12 34 56 78 becomes +31 6 12 34 56 78 internationally.
A Dutch Mobile in Four Standard Formats
Here is how one Netherlands number is written in each of the four standards:
| Format | Example | Use for |
|---|---|---|
| E.164 | +31612345678 | Databases, SMS APIs (Twilio, WhatsApp), CRMs |
| International | +31 6 12 34 56 78 | Display to a global audience, business cards |
| National | 06 12 34 56 78 | Domestic display inside Netherlands |
| RFC3966 | tel:+31-6-12-34-56-78 | Clickable tel: links on websites |
ACM, the 06 Monopoly and Pair-Grouped Formatting
The Netherlands Authority for Consumers & Markets (ACM) administers Dutch numbering under a clean split: 06 belongs exclusively to mobiles, and everything else is geographic or special-purpose. This means a Dutch phone number's type is instantly readable from the first two digits — no lookup required. 06 is a mobile, 020 is Amsterdam, 010 is Rotterdam, 070 is The Hague. The system is one of the most logically organised in Europe.
Dutch formatting convention groups mobile numbers in pairs after the initial "06": 06 12 34 56 78. This is distinct from the grouping used by French numbers (also pairs but a different prefix structure) and British numbers (no pair convention). Dutch users strongly expect this pair grouping in UI displays; grouping a Dutch mobile any other way — 06-1234-5678 or 0612345678 — reads as foreign or incorrect even if numerically identical.
Landline area codes follow a hierarchical pattern: major cities got two-digit codes (020, 010, 040 Eindhoven) while smaller areas use three or four digits. Unlike Germany, Dutch landlines have a predictable total length of 10 digits nationwide, so length-based validation is reliable once the trunk 0 is accounted for.
06 Mobiles and Landline Area Codes
Type Prefixes Digits Example Mobile 06 10 (incl. leading 0) 06 12 34 56 78 Amsterdam landline 020 10 020 123 4567 Rotterdam landline 010 10 010 123 4567 Other geographic 013–099 (excl. 06) 10 030 123 4567 Freephone 0800 10 0800 023 4567
Calling the Netherlands: Drop the 0 After +31
Calling from Dial Within the Netherlands 06 12 34 56 78 — Keep the leading 0 domestically. From the US 011 31 6 12 34 56 78 — Drop the leading 0. From any mobile +31 6 12 34 56 78
- Enter + or your country's international exit code.
- Add the Netherlands country code 31.
- Drop the leading 0 from the Dutch number.
- Dial the remaining 9 digits — e.g. 6 12 34 56 78 for a mobile.
Dutch Numbering Essentials
- All Dutch mobile numbers start with 06 — this is the only prefix used for mobiles and it never changes.
- The leading 0 is always dropped after +31: 06 12 34 56 78 → +31 6 12 34 56 78.
- Dutch convention groups mobile digits in pairs after the "06": 06 12 34 56 78 — not dashes or a single block.
- All Dutch numbers (mobile and landline) are 10 digits nationally, making validation straightforward.
Key Dutch Area Codes
Area code Region 020Amsterdam 010Rotterdam 070Den Haag (The Hague) 030Utrecht 040Eindhoven 050Groningen 024Nijmegen 076Breda
Format a Dutch Number Instantly
Enter any Dutch 06 mobile or landline in any style and get the correct +31 E.164 and pair-grouped international format.
Enter phone number with country code or select country below.
Up to 100 numbers. Include country code or select a default country below.
| Original | E.164 | International | National | Valid |
|---|
Netherlands Phone Format FAQ
How do I write a Dutch mobile number in international format?
Drop the leading 0 and add +31: 06 12 34 56 78 becomes +31 6 12 34 56 78, or +31612345678 in strict E.164 for databases and SMS APIs.
What do Dutch mobile numbers start with?
All Dutch mobile numbers start with 06 nationally (+31 6 internationally). There are no other mobile prefixes in the Netherlands — 06 is the exclusive mobile range.
How many digits does a Dutch phone number have?
All Dutch phone numbers are 10 digits in national format — mobile (06 + 8 digits) and geographic landlines (area code + subscriber number). After +31, there are 9 digits.
What is the area code for Amsterdam?
Amsterdam's area code is 020. A full Amsterdam number is 10 digits: 020 followed by a 7-digit subscriber number. Internationally: +31 20 XXX XXXX (the trunk 0 is dropped).
How do I call the Netherlands from abroad?
Dial your international exit code (011 from the US, 00 from Europe), then 31, then the Dutch number without its leading 0. From a mobile, +31 works directly: +31 6 12 34 56 78.