What is RFC3966?

RFC3966 is a standardised format for telephone numbers, represented as a Uniform Resource Identifier (URI) with the prefix “tel:” followed by a unique digit sequence. For example:

  • tel: 2345678901
  • tel: +12345678900

The RFC3966 format has a standardised structure and contains the following components:

  1. “tel:” a globally unique identifier that specifies a telephone number
  2. Country code: a numeric sequence that represents a specific country
  3. Numbering Plan Area (NPA) code: a 3-digit area code.
  4. Phone number: someone’s local phone number

Why is RFC3966 important for SMS marketing?

RFC3966 is designed to work seamlessly with mobile devices using their built-in tap-to-call functionality. It makes communication between ecommerce brands and their subscribers easier, but also helps with global compatibility—RFC3966 supports both local and international numbers, which facilitates sending SMS messages to a global audience without any manual adjustments.

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