Secure user logins globally with Infobip’s SMS OTP service
Authenticate users instantly with the world’s most reliable SMS OTP verification API. Easily reach mobile users globally through Infobip’s 800+ direct telco connections.
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POWERING CRITICAL COMMUNICATIONS FOR GLOBAL BRANDS
Why brands trust Infobip for authentication via SMS
Every day, our SMS OTP platform helps protect millions of user logins all around the world. With high delivery rates and proven reliability, we help brands keep accounts safe and make sure users can always get access when they need it.
Unrivaled delivery rates
Bank-grade security
Global reach, local feel
Built for developers, scaled for enterprises
- Smart fallback logic: If one channel fails, automatically retry via others. Ensure 100% verification success.
- Real-time analytics: Monitor delivery speeds and conversion rates instantly.
- Flexible configuration: Customize code length, expiry time, and retry limits.
Customer stories
From fintech to entertainment, brands across the globe trust Infobip platform to secure their user experience.
Spoon Radio: 80% reduction in subscriber sign-up churn with an optimized 2FA Authentication solution from Infobip .
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80%
reduction in subscriber churn .
Bukalapak: Increasing client account security with two-factor authentication .
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4-5%
increase in delivery rates .
Yousign: Increasing SMS delivery rates to authenticate signers .
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97%
delivery rates .
Kakao: Increasing new user conversion rate to more than 90% with reliable one-time PIN delivery .
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90%
increase in new-user conversion rate .
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We are very satisfied with Infobip’s delivery rates that are over 97%, and that is why they are our main provider of SMS solution for one-time pin delivery. OTP delivery is a crucial part of our business and because of high delivery rates and technical support we value our cooperation with the company very much.
Romain Pichard
Product Owner, Yousign
Verify users via SMS in 4 simple steps
User request
Code generation
Message delivery
User verification
Examples of SMS OTP use cases
Public services
Authenticating personnel accessing critical systems (e.g. police and fire departments or emergency response teams).
Delivery services
Verifying personnel and ensuring secure package handling.
Educational institutions
Securing access to student portals, course registrations, and academic resources.
Hotels and airlines
Enhancing security during online bookings, reservation changes, and loyalty program interactions.
Why SMS OTP remains the standard
Use SMS for maximum reach, and layer other channels for cost optimization.
| SMS OTP | Email OTP | WhatsApp OTP | |
|---|---|---|---|
| Reach | 100% (any phone) | High | Only app users |
| Speed | Instant | Slower (due to spam filtering) | Fast (if internet connection stable) |
| Internet connection required? | No | Yes | Yes |
| Best for | Primary two-factor authentication | Backup 2FA | Cost savings (with fallback) |
Expand your messaging channel mix – maximize conversions, minimize costs
Send time-sensitive OTP messages on the most cost-effective channel for each recipient, with failover safeguards that never let you down.
Recognized for reliability, security, and reach
Our OTP SMS service received widespread recognition within the industry, being awarded for its reliability, security, and global reach. As a trusted provider, these awards reinforce our devotion to providing top-tier security solutions that businesses can rely on.
SOC 2 Type 2 compliant
Mobile Ecosystem Forum certified
How to choose an SMS OTP provider
Choosing the right SMS OTP provider is crucial for ensuring security and reliability of the authentication process. Let’s explore the key criteria you should consider before deciding:
Deliverability and speed
Look for providers that offer guarantees in delivering SMS messages promptly to customers. Delays in OTP delivery can impact user experience and security.
Security features
Evaluate the encryption methods used by the provider. Strong encryption ensures that OTPs remain confidential during transmission. Consider data protection mechanisms, such as secure storage of phone numbers and OTPs. Ensure the provider complies with relevant regulations (e.g., GDPR, CCPA) to safeguard user privacy.
Integration
Assess how easily the SMS OTP solution integrates with your existing systems. A seamless integration process minimizes disruptions and saves time. Check if the provider offers APIs or SDKs for smooth implementation.
Pricing
Compare costs among different providers, considering initial setup fees and ongoing charges. However, note that a lower price might mean lower-quality SMS routes, which could lead to OTPs not being delivered. Scalability is essential—ensure the pricing model aligns with your expected growth.
Frequently asked questions about SMS OTP
Yes. When implemented with best practices, such as short expiry times and rate limiting to prevent brute force attacks, it is a secure standard. Infobip also offers Signals, a product that uses machine learning to detect and block artificial traffic and SMS pumping fraud to further enhance security.
Our system handles this using smart fallback features. If an SMS fails to deliver (e.g., due to network issues), the API can automatically retry via alternative channels like Voice or Email to ensure the user is never locked out. You can also configure specific failover logic, such as failing over from RCS to SMS, to guarantee delivery. Read more about failover API setup here.
An OTP, or one-time password, is a temporary code generated by a system and used to verify a single login session, transaction, or action. 2FA (Two-Factor Authentication) is the general security process that requires two forms of identification (e.g., your password + the OTP). OTP codes are one of the most popular methods of implementing 2FA. In case of SMS OTP, an SMS message is simply the delivery channel for the OTP code. You can also send OTP codes via other channels, like WhatsApp OTP, RCS OTP, or Viber OTP.
Yes. Infobip’s 2FA API lets you verify users via SMS, Email, and Voice. This allows you to create “smart routing” strategies—for example, use a Email or App push first, with SMS as a high-reliability backup. Read more about our 2FA API here.