What is the North American Numbering Plan?


The North American Numbering Plan (NANP) is a phone numbering system used in regions and countries across North America, the Caribbean, and some Pacific territories. It simplifies communication by standardizing phone numbers into a 10-digit format, eliminating confusion caused by different regional formats.

The International Telecommunications Union (ITU) assigns phone numbers a country code (for example, 1 in the US). The remaining 10 digits all have a specific meaning:

  • Numbering plan area (NPA): Also known as the area code, the NPA consists of 3 digits and stands for a region within a country. 
  • Central office code: These are the next 3 digits that indicate a smaller area within a region.
  • Subscriber number: The final 4 digits of that represent the unique code for a specific phone line or device.
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Using NANP phone numbers in your SMS marketing efforts

There are 3 benefits to using NANP phone numbers for marketing:

  1. Trustworthiness: Phone numbers with a relevant area code feel more trustworthy and foster familiarity with subscribers.
  2. Higher open rates: Because local numbers seem more trustworthy, people tend to be more interested in engaging with text messages from local numbers than generic toll-free numbers.
  3. Two-way communication: Subscribers are more likely to reply to a local number with inquiries or requests. This promotes further interaction, such as order tracking, confirmations, or support, leading to better customer experience.

Use a marketing automation platform like Klaviyo to reach out to NANP numbers via SMS. Sign up today to easily create an SMS list, segment it according to user behavior or demographics, and write and send messages in only a few clicks.

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