Standardize Phone Numbers to the E.164 Format

E.164 is an internationally recognized standard that ensures every device has a globally unique number consisting of a plus sign (+), country code, and phone number. For example, +14155552671. For best results, turn on automatic E.164 formatting for your phone numbers.

Available in: Lightning Experience

Unified Messaging for RCS, SMS, and WhatsApp is available in: Enterprise and Unlimited Editions for Marketing Cloud Growth and Advanced Editions

Not supported in Government Cloud Plus

When tracking consent for messaging channels, phone numbers are stored using the E.164 international standard format. When you enable automatic E.164 formatting, any phone number without a country code is converted to the E.164 standard based on your selected default country. These updates can help prevent delivery failures and routing errors.

You can configure E.164 phone number formatting per business unit. Setting a local default country prefix, such as +1 for the US or +44 for the UK, allows you to import local number formats that automatically align with that business unit's SMS, WhatsApp, and RCS channels.

Consent evaluation requires an exact E.164 match. When formatting is enabled, the system automatically removes special characters, spaces, and hyphens before appending the default country prefix. If the formatted number doesn't match the number in consent records, the message isn't delivered.

E.164 formatting uses a static default country per business unit and doesn't support dynamic, field-driven selection. If a business unit processes numbers from multiple countries, you must format the phone numbers in E.164 before import to prevent routing failures. You can disable E.164 formatting in Unified Messaging Setup at any time or re-enable it with a new default country.