The E.164 phone number format is the global standard for representing phone numbers in a consistent, internationally recognized way. Developed by the International Telecommunication Union (ITU), this format ensures that every phone number on the Public Switched Telephone Network (PSTN) is unique and easy to route anywhere in the world.
Correctly formatting numbers in E.164 is essential for accurate call routing, CRM synchronization, and seamless VoIP integrations. Without it, you risk failed calls, mismatched contacts, and disrupted workflows.
E.164 specifies the exact structure phone numbers must follow for global compatibility:
Structure: + [Country Code][Area Code][Subscriber Number]
Maximum Length: 15 digits
No Spaces or Special Characters: Numbers must not contain spaces, parentheses, dashes, or symbols.
Examples:
UK number 020 1234 5678 → +442012345678
US number (415) 123-4567 → +14151234567
NUACOM’s cloud-based phone system is designed for high reliability and accurate data handling. Using E.164 ensures that:
Calls Reach the Right Destination: Prevents routing errors across countries and networks.
CRM & Helpdesk Integrations Work Seamlessly: NUACOM integrates with tools that rely on E.164 for matching and storing contact data.
Contacts Stay Clean & Organized: Avoids duplicate records and incorrect caller ID matching.
Error-Free Operations: Reduces the risk of missed calls and incomplete call logs caused by formatting inconsistencies.
Global Consistency: Standardized format works across multiple regions and offices.
Integration-Ready Data: Improves compatibility with CRMs, helpdesk, and analytics integrations.
Better Caller Identification: Ensures incoming and outgoing calls display correct details.
Higher Call Success Rate: Eliminates failed connections caused by incompatible number formats.
1. Manual Entry
When adding contacts, enter the full number starting with +, followed by the country code and subscriber number.
Example: French number 06 12 34 56 78 → +33612345678
2. Preparing Bulk Imports
If uploading contacts from a CSV file, ensure every number is pre-formatted in E.164. This avoids import errors and ensures accurate caller matching.
3. Using Google Sheets for Conversion
REGEXREPLACE Function: Removes non-digit characters and prepends the country code.
Example: ="+44"®EXREPLACE(A1,"\\D","") (for UK numbers)
REPLACE Function: Removes leading zeros or prefixes.
Example: =REPLACE(A1,1,1,"")
4.8/5 stars
4.8/5 stars
4.9/5 stars
⭐⭐⭐⭐⭐
25 September, 2024
Best customer support
We needed to implement a VolP system within a very short timeframe, and NUACOM
proved to be the perfect choice. A special thanks to David and Vaibhav for their
exceptional support. Despite their busy schedules, they made time to ensure a
smooth onboarding process, understanding the urgency of our business needs.
Date of experience: September 25, 2024
By choosing NUACOM, you’re not just selecting a VoIP provider; you’re partnering with a company committed to helping you achieve seamless and effective communication. Experience the difference with NUACOM, the best VoIP
No. The format requires a continuous string with no spaces or special characters.
You risk failed call routing, broken integrations, and incomplete contact matching.
Some features may work without it, but using E.164 ensures full compatibility and best performance.
Use spreadsheet tools like Google Sheets with REGEXREPLACE or REPLACE functions to standardize numbers efficiently.
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