What is E.164 format?
E.164 format is the international way to write a phone number: a plus sign, the country code and the national number, with no spaces or symbols.
Why it matters for sales teams
The same number can be stored many ways: with brackets, dashes, dots, a leading 1 or none. To a person they look the same. To software they are different strings, which breaks duplicate checks, matching inbound calls to CRM records and syncing between tools. Storing every number in one format avoids that.
Strictly speaking, E.164 is the international numbering plan published by the ITU, the United Nations agency for telecommunications. It sets the structure of a number: a country code followed by the national number. Writing it with a leading plus sign is how software usually stores it.
Example
A US number written as (512) 555-0147, 512-555-0147 or 1 512 555 0147 becomes +15125550147 in E.164 format. The 1 is the country code shared by the countries of the North American Numbering Plan, including the US and Canada.
E.164 vs local formats
Local formats are written for people and change from country to country. E.164 is written for systems and works the same everywhere, which is why phone number validation and two-way sync setups often normalize numbers to it.