If you’ve received a call or text with a +31 prefix, you are being contacted from the Netherlands. Unlike a domestic area code, the +31 code is the international calling code (or country code) used to reach any phone number within the Netherlands, including its major cities like Amsterdam, Rotterdam, and The Hague.
This article, written by a telecommunications expert, provides a clear, actionable guide on dialing the Netherlands, lists the main city codes you’ll need, and offers crucial advice on identifying potential scams originating from the +31 country code.
What is the +31 Code?
The code +31 is the international country calling code for the Netherlands. It must be dialed before the local city code and local number when calling the Netherlands from any other country worldwide.
The Netherlands uses a closed numbering plan with a National Significant Number (NSN) length of 9 digits. Dutch numbers are 10 digits long in total when dialed domestically (including the leading ‘0’ trunk prefix). When dialing internationally using the +31 country code, you must drop the leading ‘0’.
How to Dial the Netherlands (Step-by-Step)
To successfully place a call to a landline or mobile number in the Netherlands from an international location, follow this dialing format:
| Part of the Number | Example (Calling Amsterdam) | Notes |
| 1. International Exit Code | 00 or + | Varies by country (e.g., U.S./Canada is 011, most of Europe is 00). The + sign works from most mobile phones. |
| 2. Country Code | 31 | The international code for the Netherlands. |
| 3. Area or Mobile Code | 20 | This is the Amsterdam area code, with the leading ‘0’ dropped (domestic code is 020). |
| 4. Local Number | XXXX XXXX | The subscriber’s unique local number. |
| Final International Format | +31 20 XXXX XXXX | Total number length (excluding the ‘0’ prefix) is typically 9 digits. |
Important Note for Mobile Numbers: Mobile phone numbers in the Netherlands begin with 06 when dialed domestically. When calling from abroad, you would use +31 6 followed by the remaining 8 digits of the number.
+31 Area Codes for Major Dutch Cities
Within the Netherlands, fixed-line telephone numbers are assigned geographical area codes that are 2 or 3 digits long. Here are some of the most populated cities and their associated codes (remember to drop the leading ‘0’ when dialing internationally using +31):
| City | Domestic Area Code | International Area Code (After +31) |
| Amsterdam | 020 | 20 |
| Rotterdam | 010 | 10 |
| The Hague (Den Haag) | 070 | 70 |
| Utrecht | 030 | 30 |
| Eindhoven | 040 | 40 |
| Groningen | 050 | 50 |
| Breda | 076 | 76 |
| Haarlem | 023 | 23 |
Is a Call from +31 a Scam? Safety & Security
If you receive an unexpected call, text, or WhatsApp message with the +31 country code, it is important to exercise caution. While many calls are legitimate (from businesses, friends, or family), this code has been increasingly linked to international phone scams.
Common Scam Types Associated with +31
- Wangiri/One-Ring Scams: Scammers call and hang up after a single ring. The goal is to prompt you to call back out of curiosity. Since +31 is an international number, you will be charged premium international rates for the call-back, and the scammer earns a portion of that fee.
- Impersonation Scams: Scammers will call, often using a mobile number (which begins with +31 6…), and claim to be from a government agency (like the “Department of Justice”), a bank, or a major shipping company (like FedEx or DHL). They often demand personal information (like a “social security number,” which is the BSN in the Netherlands) or urgent payment.
- WhatsApp/Text Message Scams: A common international scam involves a text message claiming to be from a relative or child using a “new number” (a +31 mobile number). They will claim their old phone is broken and urgently need money transferred to a new account.
How to Protect Yourself
- Do not call back: Never return a call to an unexpected international number you don’t recognize.
- Hang up immediately: If the call is a robocall or if the person immediately starts asking for personal data, hang up. Legitimate government and financial institutions do not make unsolicited calls demanding personal information or immediate payments.
- Verify the source: If the caller claims to be a company, look up the official contact number for that company and call them directly to verify the story.
- Check the full number: Numbers in the Netherlands are almost always 10 digits in total length (including the initial ‘0’ for domestic calls, which is dropped for +31). An unusually short or long number may be a manipulated or spoofed number.
Frequently Asked Questions (FAQ)
What is the difference between a country code and an area code?
A country code (+31) is a 1-to-3-digit code required to call a different country. An area code (e.g., 20 for Amsterdam) is a 1-to-4-digit code required to call a specific geographical area or city within that country. You must use both to complete an international call.
How do I call a Dutch mobile number from the USA?
To call a mobile number in the Netherlands from the USA, you must dial:
011 (US Exit Code) + 31 (Netherlands Country Code) + 6 (Mobile prefix, without the domestic ‘0’) + 8-digit mobile number.
The number will look like this: 011 31 6 XXXX XXXX.
Is the country code +599 also part of the Netherlands?
Yes, the country code +599 is used for the Caribbean Netherlands (Bonaire, Sint Eustatius, and Saba). While these islands are special municipalities of the Netherlands, they use a separate country code because they are geographically located in the Caribbean and are not part of the main European numbering plan (+31).
Why am I getting calls from +31 numbers on WhatsApp?
Receiving calls from a +31 number on WhatsApp is often part of an international scam known as the “Hi, Mom” or “Hi, Dad” scam. Scammers purchase an inexpensive international SIM card (like a Dutch one) and use it to contact people worldwide, pretending to be a family member who has lost their phone and is in urgent need of money. Do not engage, verify their identity through another channel, and block the number.
Conclusion
The prefix +31 is definitively the international country code for the Netherlands. It is the essential first step when placing an international call to any Dutch landline or mobile phone. While the code itself is harmless, a surge in phone scams originating from internationally based numbers—including those in the Netherlands—means you should remain vigilant. Always verify the identity of an unknown caller or sender, and never return calls to suspicious one-ring numbers.
