Phone Verification API

Secure, single-use voice or SMS verification codes add reliable security to your systems. As the leaders in voice and SMS verification, TeleSign helps you deliver personalized customer safety anywhere on the globe.

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Protect account access
Verify transactions
Prevent fake users

Trusted Security

Two-factor authentication is the foundation of fraud prevention and account security. Prevent fraudulent account creation and make sure that your digital community is safe, secure, and streamlined with easy to implement one-time passcodes and two-factor authentication.

Unmatched Global Coverage
Reach more customers with 120+ optimized points-of-presence and 700+ direct-to-carrier routes​.
Exceptional Reliability
Optimal performance with higher successful delivery rates than any leading competitor.
5-Star Customer Service
Premium customer support to strengthen communication, reduce costs, and ensure seamless customer interaction.

Protect Your Customer and Your Business

Identify valid phone numbers, flag suspicious users, and prevent fraudulent activity with accurate phone verification data and key user identity attributes.

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Verify Transactions

Ensure your users are who they say and stay PDS2 compliant when customers change important account information, access credit card details, transfer funds, or make payments.

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Prevent Fake Accounts

Mitigate new account registration fraud and attempts to create spam accounts in bulk by requiring two-factor authentication. TeleSign makes it easy to verify your end-users – even when SMS isn’t available.

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Trusted by Top Companies

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Verification in Action

Our phone number verification API offers fast, easy, and flexible SMS and voice verification to deliver on even the most complex use cases. Get up and running fast with clear documentation, user-friendly developer tools, comprehensive data reports, and the white-glove customer service.

High Quality, Direct-To-Carrier Routes
TeleSign’s direct access to hundreds of carriers and waterfall approach across different routes ensures exceptional delivery and conversion rates.
Secure, Time-Based, One-Time Passcode (TOTP)
Block illegitimate accounts and verify users in real time with one-time SMS verification codes to authenticate identities and verify transactions.
Traffic Monitoring
Automatically flag anomalies in traffic type and volume to help prevent and fraud malicious attacks.
Reliable Global Coverage
Our extensive reach provides the most coverage and best-in-class message delivery to users in 87 countries and territories to keep your users protected, wherever they are.
Answering Machine OTP Delivery Prevention
Automatic answering machine detection prevents your one-time passcodes from being accidently left on vulnerable voicemail systems.
Dynamic CallerID
Use your preferred caller IDs so your customers know who is calling.

User Registrations

Send new customers a one-time SMS or voice passcode to verify that they are the person who just registered for an account.

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Password Resets

Stop account theft in its tracks and ensure that only your customers can reset their passwords by providing a one-time SMS or voice passcode to the user’s phone before approving any password changes. 

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Transaction Confirmation

Verify customers’ transactions with a one-time passcode sent via SMS or voice, which they can use to confirm the purchase or transfer.

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Ready to deliver
a trusted experience?

We’re ready to help you:
✓ Streamline & secure onboarding
✓ Reach your customers on the channels they trust
✓ Safeguard your customers’ accounts
✓ Establish comprehensive fraud protection