Understanding E.164 Phone Number Format

What is E.164 Format?

E.164 is an international standard for phone number formatting established by the International Telecommunication Union (ITU). It provides a uniform way to represent phone numbers globally, ensuring they can be correctly interpreted by telecommunication systems worldwide.

The E.164 format has a simple structure:

• A plus sign (+) at the beginning
• The country code (1-3 digits)
• The national number (up to 15 digits total including the country code)

For example, a US phone number in E.164 format would look like: +14155552671

Why E.164 Matters

Using E.164 format is crucial for several reasons:

1. Global Compatibility

E.164 numbers work across all international telecommunication networks. When you store phone numbers in this format, you ensure they can be dialed correctly from anywhere in the world.