Whenever you add a new friend on WhatsApp from Malaysia, you see a +60 prefix. If you text someone in Indonesia, it is +62, and for Singapore, it is +65. Meanwhile, if you message a friend in Vietnam, the number suddenly jumps to +84.
Have you ever wondered where these random numbers come from? Why didn't Southeast Asian countries get a simple "+1" or "+2"?
The “Mastermind” Behind the International Dialing Codes
The whole system exists thanks to an agency under the United Nations called the International Telecommunication Union (ITU). Decades ago, when international calling started booming, the ITU realized they needed a structured way to route phone calls across borders without mixing them up. To solve this, they divided the entire world map into 9 distinct calling zones.
According to The Guardian, the very first list of international codes appeared in a document called the Red Book. At first, this book only suggested codes to connect phone calls across Europe. Furthermore, European countries still use most of those original codes today.
As international travel and business grew, the system needed to expand. In 1964, the ITU released the Blue Book. This new version officially divided the entire world map into the dialing zones we use now.
The ITU gave the largest landmasses at the time, like North America and the Soviet Union (now Russia), simple or single-digit codes. Smaller countries and territories received two-digit or three-digit codes. Today, the system even sets aside special codes for satellites in space to keep our global networks running.
Global Calling Zones
Here is how the ITU split the world into 9 distinct zones:
- Zone 1: United States and Canada
- Zone 2: Africa, Greenland, and the British Indian Ocean Territory (BIOT)
- Zone 3: Europe
- Zone 4: Europe
- Zone 5: South America and Central America
- Zone 6: Southeast Asia, Oceania, and Australia
- Zone 7: Russia and Kazakhstan
- Zone 8: East Asia and parts of South Asia
- Zone 9: West Asia, the Middle East, Central Asia, parts of South Asia, and Eastern Europe
Dialing Codes in Southeast Asia
The ITU placed most of Southeast Asia, along with Australia and the Pacific islands, into Zone 6. This is why a majority of ASEAN nations share the same starting digit.
Once the ITU assigned the number "6" to this part of the world, they gave each country a unique second digit to complete their code. Here is how the neighborhood looks:
- Malaysia: +60
- Indonesia: +62
- The Philippines: +63
- Singapore: +65
- Thailand: +66
- Brunei: +673
As you can see, not every country in Southeast Asia fits into Zone 6. Because of historical ties and how the ITU distributed lines over the years, a few mainland neighbors ended up in different zones.
For instance, Vietnam (+84), Cambodia (+855), and Laos (+856) belong to Zone 8, a region they share with East Asian neighbors like China and South Korea. Meanwhile, Myanmar (+95) sits in Zone 9, which mostly covers South Asia and the Middle East.
