<iframe src="https://www.googletagmanager.com/ns.html?id=GTM-M74D8PB" height="0" width="0" style="display:none;visibility:hidden">
Loading
Skip to NavigationSkip to Main Content
How Does Okta Perform Validation for Phone Numbers Used under SMS/Voice Call Factor
Okta Classic Engine
Multi-Factor Authentication
Overview
This article provides information on how Okta leverages the Phone factor, SMS/Voice Call factor.
Applies To
  • Multi-Factor Authentication (MFA)
  • Phone Factor
  • Okta Classic Engine
Solution

During the enrollment process, a screen appears, allowing the selection of a country. Upon selecting a country, the prefix auto-populates, followed by an option to input the phone number and proceed with enrollment (if done via the UI).

The phone numbers leveraged for the SMS/Voice Call factor need to respect the E.164 standard. The ones that fall outside of the standard may work. However, this depends on variables such as the device in use or the carrier. E.164 numbers can have a maximum of fifteen digits and are usually written as follows: [+][country code][subscriber number including area code]. Phone numbers that are not formatted in E.164 may work, but it depends on the phone or handset that is being used as well as the carrier from which the call or SMS originates.

Quickly verify users via SMS, Silent Network Auth, voice, WhatsApp, TOTP, push, Silent Device Approval, and email by using this Twilio link.

Related References

Loading
How Does Okta Perform Validation for Phone Numbers Used under SMS/Voice Call Factor