Top 7 SMS OTP service providers to secure your customers | How to choose the right one?

May 22, 2024
Top 7 SMS OTP service providers to secure your customers | How to choose the right one?

At the most practical level, your SMS OTP service provider should give you all the features you need to deliver OTPs to your customers. 

Every SMS one-time passcode (OTP) service provider is different. 

Some providers offer a more extensive network of carrier partnerships, enabling you to send OTPs worldwide with better deliverability. Others focus on building a strong infrastructure to manage domestic OTP deliveries. 

OTP providers also vary in the availability and flexibility of APIs and SDKs for integration into existing systems, impacting the ability to customize and implement the OTP experience in your existing tech stack. 

Choosing the right OTP provider requires defining your requirements and goals, vetting various providers, and understanding how well each solution works with your existing tech stack. 

In this guide, we’ll explain the features you need to look for in an SMS OTP service provider, the top seven most popular SMS OTP service providers in the market, and how to choose the right one for your needs. 

What features should I look for in an SMS OTP service provider?

Consider eight features when choosing an SMS OTP service provider. 

  • Time-to-deploy 
  • SMS OTP conversion rates
  • Fraud detection
  • Security and compliance
  • Analytics and tracking
  • Integrations
  • Customer support
  • Price

1. Time-to-deploy 

Developers already have enough on their plates— and adding a complicated tool t that requires intensive onboarding and implementation is counterproductive to achieving your other development needs. 

When selecting an OTP provider, look for services that require minimal setup. This will allow your team to start sending OTPs with little to no downtime. 

Your SMS OTP service provider should also provide clear documentation and SDKs that make it straightforward for developers to integrate OTP with your platforms, significantly reducing the time and resources needed for deployment.

2. SMS OTP conversion rates 

One of the most frustrating experiences a customer can have is receiving a delayed OTP, or worse, not receiving an OTP at all. Delayed or undelivered OTPs can cause anxiety, potentially leading the customer to abandon the transaction or lose trust in your brand. 

Verify that an SMS OTP provider has high delivery rates to ensure that your customers can receive and act upon OTP messages.

3. Fraud detection

In international markets, OTPs in SMS and voice channels are particularly susceptible to SMS Pumping fraud. 

Advanced fraud detection should include dynamic risk assessment algorithms that adapt to emerging threats and unusual patterns. 

4. Security and compliance

When assessing the security and compliance of an OTP service provider, there are two key aspects you need to consider: data encryption and regulatory compliance. 

End-to-end encryption ensures that an OTP is encrypted at the origin and only decrypts at the receiver’s device. This protects the OTP message from being intercepted or read by hackers. To verify the robustness of the encryption, look for an OTP service provider that uses recognized standards like AES (Advanced Encryption Standard) with a suitable key length (e.g., 256-bit).  

Additionally, look for OTP service providers that adhere to data protection regulations like the General Data Protection Regulation (GDPR) in the European Union, the California Consumer Privacy Act (CCPA), and the Health Insurance Portability and Accountability Act (HIPAA) as they are mandatory for different countries. 

5. Analytics and tracking

Choose an SMS OTP service provider that offers detailed analytics and tracking. Real-time insights into OTP delivery rates and failures help identify issues as they arise. 

Custom reports with a trend analysis of KPIs, such as success rates of OTP deliveries across different regions, can highlight areas for improvement, whether in technology or carrier partnerships. You can also leverage these reports to make strategic decisions and draw behavioral insights. 

6. Integrations

Even the most robust OTP provider must play well with your existing tech stack. Think about which platforms you need your OTP tool to communicate with. Does this OTP solution fit your long-term technological needs? 

Plivo, for example, integrates with most popular tools including Zapier, Microsoft Power Automate, Integromat, Pipedream, Integrately, GitHub Actions, EngageBay, and more. 

7. Customer support

Look for an SMS OTP service provider that is available 24/7. This level or service translates to immediate assistance, minimized downtime, and enhanced reliability. Having multiple support channels, such as email, phone, web-based chatbots, and SMS, will also provide more convenience, accessibility, and personalization for your company. 

8. Price

There’s no getting around pricing. Look for an OTP service provider with clear, straightforward pricing. Most OTP providers offer multiple pricing plans; look for one designed to scale with your business as you grow. Check out Plivo’s pricing.

The 7 best SMS OTP service providers for security and reliability

Here are our top seven picks for the best OTP service providers. Read a detailed analysis of why we chose these platforms below. 

1. Plivo 

Key features

  • Turnkey single-API solution: All you need to do is integrate using a single API with Plivo and it’ll take care of the heavy lifting. For instance, Plivo keeps numbers ready for usage, so customers do not need to purchase any numbers separately. Bottom line: Plivo customers can conveniently use a secure solution without worrying about compliance issues. 
  • Multichannel support: Plivo supports both SMS and voice OTP to ensure businesses have the flexibility they need to authenticate users. 
  • High deliverability: Verify API enjoys specialized routes from carriers that are not available with the SMS API. It also uses intelligent routing to identify optimal routes and number types for enhanced conversions. Plivo also ensures sender ID and template compliance to ensure carriers do not fail them due to compliance issues.   
  • Built-in fraud control: Plivo’s Fraud Shield includes an autopilot mode to help you monitor your messaging patterns, build thresholds for each country, and automatically send alerts with irregular patterns. 

You can fine-tune and override messaging throughput thresholds for each country and access an in-built reporting to evaluate your cost savings from preventing fraud attacks using Fraud Shield. 

  • Support: Premium 24-hour support, comprehensive documentation, seven global points of presence, and 99.99% uptime SLAs are available. 
  • No additional costs: Plivo has straightforward pricing plans where you only pay for what you use. There are no charges for authentication, regulatory compliance, fraud shield, and SMS verification, making it an ideal solution for those on a modest budget. 


  • Supports SMS OTP delivery in 220+ countries 
  • High deliverability rates, minimizing SMS failures
  • Customizable OTP templates for a personalized user experience
  • Detailed analytics for tracking OTP success rates
  • Robust security features protect data integrity
  • Comprehensive API and documentation support ease of integration
  • Scalable solutions cater to businesses of all sizes
  • 99.99% uptime SLAs available with 24-hour support 


  • The vast array of features can be overwhelming for new users.

Most suitable for Companies that need a scalable, customizable SMS OTP solution with extensive integration capabilities, security, and reliability. G2 rating: 4.5 stars, 724 reviews 

2. Twilio

G2 rating: 4.2 stars, 467 reviews

Key features

  • Multichannel authentication support: Twilio provides APIs that enable you to send OTPs through SMS, passkeys, WhatsApp, email, voice, and TOTP (authenticator apps like Authy and Google Authenticator), going beyond traditional email and website communication.
  • Fraud monitoring: Twilio uses one API endpoint to validate users and detect fraud. It also lets you customize geo-permissions, rate limits, and other fraud controls. 


  • Wide range of additional communication channels available
  • Extensive API for custom integrations and workflow automation
  • Fraud detection and security features to protect customer data
  • Real-time analytics dashboard to monitor and optimize OTP deliveries
  • Global reach with localized number support


  • Steeper learning curve due to platform complexity
  • Pricing can become expensive as usage scales.

Most suitable forTech-savvy businesses and developers seeking a robust, customizable OTP solution.


G2 rating: 4.8 stars, 6 reviews  

Key features

  • Multichannel support: supports SMS, email, and voice OTP. 
  • Live analytics: It gives detailed analytics about OTP delivery, failure, and latency reports. 


  • Cost-effective solution for businesses on a tight budget
  • User-friendly platform ideal for those new to OTP services
  • API support for straightforward integration
  • Quick and easy setup with minimal configuration required
  • Responsive customer support team


  • Limited advanced features for complex implementations
  • Somewhat restricted global coverage compared to larger providers

Most suitable forStartups and small to medium businesses looking for an affordable, reliable OTP service with basic features.

4. Exotel

G2 rating: 4.3 stars, 80 reviews

Key features

  • Real-time analytics: Exotel provides real-time analytics and delivery reports, allowing businesses to track the status of each OTP code sent. 
  • Customizable OTP timers and lengths: Exotel allows users to customize the length of the OTPs and set timers for how long an OTP is valid. 


  • Simple and intuitive user interface
  • A reporting dashboard with conversational AI 
  • An extensive reach in the Asia-Pacific (APAC) and Southeast Asia (SEA) 
  • High delivery speed for OTPs


  • Limited global presence 

Most suitable forBusinesses primarily operating in APAC & SEA, as they have an extensive network in this region.

5. SMSCountry

G2 rating: 4.8 stars, 2 reviews  

Key features

  • Quick integration: SMSCountry allows you to send OTPs directly from anywhere with an easily integrable SMS API that supports several applications through SDK, XML, Web, and HTTP-API plug-ins.
  • Compliance and security: The OTP provider is powered by 100+ direct-to-carrier connections in 180+ countries, enabling users to send OTPs internationally. 


  • Easy to use and integrate, reducing time to market
  • Supports 180+ countries
  • Cost-effective for businesses mindful of budget constraints
  • Real-time delivery reports for tracking OTP status
  • Dedicated account management and 24/7 customer support


  • Limited functionality for advanced customization needs
  • Fewer global direct carrier connections may affect delivery in certain regions.
  • No option to add team members from the dashboard

Most suitable for SMBs seeking a reliable, no-frills basic OTP service that's both affordable and easy to implement.

6. MSG91

G2 rating: 3.9 stars, 47 reviews  

Key features

  • Built-in IP security: The OTP service provider comes with in-built IP data security that ensures the flow is halted when an unusual login is attempted to prevent potential fraud activities. 
  • Multichannel support: MSG91 supports multiple channels including SMS, email, Voice, and Whatsapp. 


  • Robust APIs for flexible OTP service integration
  • Comprehensive analytics for insights into OTP performance
  • Global coverage ensuring worldwide OTP delivery
  • Advanced data security protocols for customer data protection
  • Scalable pricing model that accommodates growing businesses
  • Exceptional uptime and reliability track record


  • Pricing transparency could be improved for clearer budget planning.
  • The platform's extensive features present a learning curve.
  • Limited reports—only offers a pre-selected timeframe for accessing reports. 

Most suitable forBusinesses that need multichannel support with other basic functionalities of an OTP provider.

7. TeleSign

G2 rating: 4.5 stars, 4 reviews 

Key features

  • Global coverage: Telesign’s verification API can authenticate customers across 230 countries and over 80 languages. 
  • Dynamic routing: The OTP provider’s API intelligently routes messages using the most effective routing available to provide high-speed delivery. 


  • Extensive global network for reliable OTP delivery across different regions
  • Support for a wide range of languages and localizations
  • Developer-friendly APIs and SDKs for easy integration


  • Inflexible pricing plans with plenty of friction in free trials 
  • Significant delay in receiving OTPs 
  • Lacks accurate number validation 
  • Doesn’t support its entire list of countries and numbers 

Most suitable for Startups and small businesses needing a simple, budget-friendly OTP solution.

How to choose an SMS OTP service provider?

There is a wide range of SMS OTP service providers on the market right now—but how do you decide which one meets your needs best? 

If choosing an OTP provider feels daunting, here are six steps to help: 

Step 1: Determine your OTP requirements and goals

Before diving into the selection process, get clear on your specific needs for an OTP service. Consider things like the data security level of your application, the volume of OTPs you'll need to dispatch, and whether you anticipate significant growth as this will require a scalable solution. 

Step 2: Look at key features

Jot down a list of the must-have and nice-to-have features you need from your OTP provider, like high deliverability rates, speed of OTP delivery, the ability to customize your OTP messages, and authentication flows. 

Step 3: Research the best OTP service providers

Begin your search by compiling a list of potential OTP providers. Read online reviews, testimonials, and case studies to explore each provider's reputation. 

Step 4: Set your OTP provider budget

Seek out pricing plans that offer transparency and don't hide fees in the fine print. Consider how the pricing structure fits your expected volume of OTP messages and whether the provider offers the scalability you need without increasing costs.

Step 5: Check for integration support

Look for providers that offer robust support for integration, including SDKs, APIs, and comprehensive documentation. These tools and resources will significantly smooth the integration process and reduce the time to deployment.

Step 6: Test, analyze, and report on ROI

Once you’ve set up your new OTP system, take measures to determine its return on investment. The goal is to have an efficient tool with a positive ROI. 

The bottom line is that regardless of which OTP service provider you choose, it must deliver on your goals. It should give you complete control and flexibility over how, when, and where you want to send OTPs.  

Get started with Plivo today

Choosing the right SMS OTP service provider involves considering key factors. Start by understanding your business’s needs and goals, listing out specific of your must-have and nice-to-have features like customization, global presence, and customer support. 

Think Plivo might be the perfect OTP SMS service provider for your needs? Find out today with a trial


What is OTP?

OTP stands for one-time password. It is a code that you can only use once to log into a website or app or to confirm a transaction. It's sent to your mobile phone or email and adds an additional layer of security because even if someone knows your account password, they won't have the OTP code. 

What is an SMS OTP service provider?

An SMS OTP service provider is a company that creates and sends one-time passwords for other businesses. If a business wants to implement two-factor authentication with OTPs, it uses an SMS OTP service provider to generate and send these SMS messages to its customers' phones, emails, or other digital accounts automatically.

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