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WhatsApp OTPs: Send one-time passwords on WhatsApp

Man receiving WhatsApp OTP on mobile device
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When it comes to keeping online accounts secure, one-time passwords (OTPs) are crucial. Many businesses depend on OTPs to ensure only authorized users access their accounts. Typically, these messages are sent via SMS, but they can also be sent through WhatsApp. With WhatsApp OTPs, a unique passcode is sent to a user’s registered WhatsApp phone number. It’s a quick, easy, and secure way for them to verify their identity and carry out transactions.

In this blog, we’ll explore how OTPs work on WhatsApp, guide you through how to set up your business to send them, and then delve into several enterprise use cases. Let’s get started!

Understanding WhatsApp OTP

WhatsApp OTPs are used as a form of two-factor authentication (2FA) to verify a user’s identity during account logins, transactions, or other sensitive actions. Using WhatsApp to send these messages adds an extra layer of security compared to other channels, ensuring end-to-end encryption, high delivery rates, and cost-effectiveness.

WhatsApp one-time password example

A WhatsApp OTP is a unique code sent to a user’s phone number. It expires after one use or a short time, adding security to the login process.

Whether you (or your customer) are checking a bank balance or buying something online, an OTP message sent via WhatsApp can help keep personal information safe from hackers and cyber threats.

And the best part? For the user, the process is straightforward and instant. Instead of having to jump through hoops to prove who you are, you just get a code on WhatsApp that you can use to confirm your identity. 


What’s the difference between SMS and WhatsApp OTP?

As many as 93% of global enterprises use some type of SMS OTP verification. That’s a lot! So, you may be thinking that the only difference between SMS and WhatsApp OTPs is that one is sent as a text message and the other via a WhatsApp chat. But there’s more to it than that. Let’s break down the differences.



WhatsApp OTP 


Available on all mobile phones, including non-smartphones 

Requires users to have a smartphone and have standard WhatsApp installed 


Lacks full encryption, but still offers a solid level of security (it’s better than having no protection in place) 

Messages are end-to-end encrypted  


Almost instant; delivered over mobile network infrastructure 

Almost instant; relies on internet connectivity 

User experience 

Depends on SMS inbox organization and readability 

Integrated within the WhatsApp chat interface 

Understanding these differences can help you make informed choices about which OTP authentication method suits your needs – and your customers’ needs – best.

Still on the fence about which route to take to reach all your customers? Here’s a tip: With Conversation API, sending WhatsApp OTPs is scalable because it offers fallback verification to SMS or another preferred messaging channel.

How to send a WhatsApp OTP

Sending a WhatsApp OTP is simple, but you’ll need a WhatsApp Business Platform account to do it. That’s because you can only send OTPs using an Authentication template in WhatsApp Business API. If you’re using the free WhatsApp Business App, unfortunately you won’t be able to send OTPs through WhatsApp.

As an enterprise, your best bet to send OTPs via WhatsApp is to choose a WhatsApp Business Solution provided by a Business Service Provider (BSP). It’s the easiest way to access an API to send OTPs through WhatsApp, and setup is a breeze. Plus, using a BSP offers a few added perks – like high messaging throughput, automatic fallback to SMS if WhatsApp connection is lost or the recipient doesn’t have an active WhatsApp account, and options to integrate other channels like contact centers, chatbots, and more.

Here’s a quick and easy three-step process to get started.


1. Set up a Meta Business Manager account

First and foremost, you'll need to set up a Meta Business Manager account. Here, you’ll fill in information about your business and will be able to add other people and assets to your account.


2. Sign up for a Sinch Dashboard account and set up Conversation API

Next, you’ll want to set up Sinch Conversation API. Getting started with Sinch is super simple:

  1. Sign up for a free account on the Sinch Customer Dashboard

  1. Once you’ve created an account and logged in, select Conversation API from the left-hand menu. 

  1. Review and agree to the terms and conditions and click “GET ACCESS” to proceed. 

  1. Follow the simple instructions and choose WhatsApp from the available channels.

For more documentation, check out how to get started with Conversation API.


3. Submit your Authentication message templates to WhatsApp for approval

Finally, to send any business-initiated conversations via WhatsApp (like one-time passwords) you must have two things:  

  1. Subscriber opt-in 

  1. Approved templated messages in WhatsApp Business

WhatsApp usually approves templates quickly – within two minutes in most cases. Regardless, we always recommend that businesses submit templates promptly to allow for potential rejections, giving time to make necessary changes and resubmit.

For OTPs, you can either use an existing OTP template or create one from scratch. Check out more technical documentation on setting up WhatsApp templates in Conversation API.

Benefits of using WhatsApp for OTPs

There are several advantages for enterprises to send one-time passcodes through WhatsApp. Let’s go through a few of them.


Better security

When you use WhatsApp to send OTP authentication messages, you’re boosting security for both you and your customers because WhatsApp messages are end-to-end encrypted.

Plus, having an OTP code delivered right in a WhatsApp chat adds a layer of security because of WhatsApp’s own measures to ensure that the rightful account owner can access their messages.


Ease of use

WhatsApp’s familiar interface can help minimize friction in the verification process and reduce the learning curve for users. This makes verification quick, intuitive, and hassle-free.


Global reach

WhatsApp has over two billion users – no one can argue that’s a massive worldwide audience!

If you’re a global brand looking to reach customers, using WhatsApp is a no-brainer. WhatsApp is huge in Latin America, India, much of Europe and Africa, and some countries in Asia, and is the number one messaging app in many countries as well.

Map showing where WhatsApp is the #1 messaging app

Map shows countries where WhatsApp is the number one messaging app. Last updated September 2023.

Tip: If you’re in North America, learn about and join our WhatsApp OTP beta program using Verification API. This is an excellent solution to help your business save money by using WhatsApp and other affordable methods like Flash Call.


Interactive messaging

Another huge plus of sending OTPs via WhatsApp is that it offers more ways to interact. Brands can use WhatsApp not just for OTP messages, but also for things like customer service and special offers. And if you’re already using WhatsApp Business API to send marketing or customer service notifications, adding authentication templates is easy and straightforward, and only requires submitting additional templates for approval.

Let’s put ourselves in a customer’s shoes and look at what this might look like from their perspective: You get an OTP to log in. Then, if you have a question, you can chat with customer service in the same app. You might also even get a promotion on WhatsApp reminding you to complete a purchase. With WhatsApp, everything you need to engage with your favorite brand is right at your fingertips!


SMS fallback

Sending WhatsApp messages through a BSP like Sinch means that if a message can’t be delivered, it’ll automatically switch to SMS or another messaging channel. You don’t need to do any extra integration – just activate the channels in Conversation API, and it handles the rest. This not only simplifies the process but future-proofs your business against any changes or challenges that may arise in the market.

5 benefits of using WhatsApp for OTPs

Sending OTPs via WhatsApp offers enterprises enhanced security, ease of use, global reach, interactivity, and automatic SMS fallback.

Use cases for WhatsApp OTPs

WhatsApp is great for enhancing verification and authentication processes. But what does that look like in real life? Here’s a glimpse into some typical enterprise use cases for WhatsApp OTPs.


1. User registration

New user registration becomes seamless and secure with WhatsApp OTPs. During the registration process, you can ensure each user’s identity is authenticated via WhatsApp before granting access. This way, users receive their verification code directly to their WhatsApp account for a hassle-free registration experience!


2. Transaction confirmations

Using WhatsApp OTPs for transaction confirmations adds an extra layer of security to financial transactions. When a transaction is initiated, users can receive an OTP on WhatsApp, ensuring that only authorized individuals can complete it. This helps prevent unauthorized access and keeps users’ financial information safe and sound.

Verification messages sent via WhatsApp can also help financial institutions shift to conversational banking. This means they can send OTPs, provide customer service, and even offer personalized banking services all through the same messaging app.


3. Password reset

WhatsApp OTPs can simplify password reset requests by giving users a secure, convenient way to regain access to their account. When they receive an OTP code directly in their WhatsApp messages app, users can quickly reset passwords without the need for manual verification steps.


4. Account recovery

Account recovery becomes super straightforward with WhatsApp OTPs. Users can verify their identities and regain access to their accounts by receiving authentication messages directly in their WhatsApp account.


5. Two-factor authentication (TFA)

WhatsApp OTPs help fortify users’ accounts with an extra layer of protection against unauthorized access. This helps add a layer of security and helps build trust by instilling confidence in users about the safety of their accounts.


6. Subscription services

Do you provide a software service on a subscription basis? Or maybe you offer another type of subscription-based service? Subscribing to these services becomes much more convenient with WhatsApp OTPs. Users get a code on WhatsApp, allowing them to quickly verify their identity, keeping things simple and safe for their subscription account.

Make WhatsApp OTPs a part of your strategy

So now you know: WhatsApp isn’t just for chatting with your friends and family – it can also be a secure way for your business to verify identities via one-time passwords.

Businesses that use WhatsApp for authentication can ensure safe logins and transactions using end-to-end encrypted, global reach. It’s not only convenient – it can enhance security and trust in your customers’ interactions.

Want to get started? Our comprehensive WhatsApp API guide offers step-by-step insights into incorporating WhatsApp into every aspect of your customer journey.

Download a step-by-step guide to WhatsApp business messaging e-book

If you’re ready to talk about your WhatsApp Business Solution, get in touch. Our team is excited to help you build a conversational messaging strategy your customers will love!