How to Send OTP Via WhatsApp: A Complete Guide
Published: Aug 19, 2025
Your customer is about to complete a high-value purchase. They’re seconds away from checkout when they’re asked to verify their identity. The OTP arrives—not through email, not through SMS—but directly on WhatsApp, the app they already have open. In less than a minute, the transaction is confirmed. That’s the speed and efficiency of WhatsApp OTP, and the front line of defense against fraud, account breaches, and unauthorized activity.
Sending OTPs through WhatsApp combines solid security with unmatched convenience. With over two billion people using WhatsApp worldwide, it’s no surprise that businesses are shifting from traditional OTP channels to this platform. End-to-end encryption, global reach, and real-time delivery make WhatsApp a top choice for verification.
In this guide, you’ll learn how to send OTPs on WhatsApp the right way using the Dexatel platform. We cover key benefits, the step-by-step setup process, and best practices so that every code reaches your users securely and instantly.
Why Use WhatsApp for OTP Messages?
Choosing WhatsApp for one-time password delivery means you want to optimize performance, reach, and data integrity for mission-critical authentication. Like SMS, WhatsApp has a high open rate of 98%, far exceeding email’s 35.63%. For OTP WhatsApp, this means faster user verification, reduced drop-offs during sign-up or checkout, and fewer failed transactions.
With over 2 billion active users across more than 180 countries, WhatsApp offers near-universal coverage. Businesses can send OTPs internationally without relying on multiple local SMS providers—an especially valuable factor for regions where SMS is delayed.
All WhatsApp messages are protected with end-to-end encryption so that only the intended recipient can view the OTP. Combined with transport security protocols, this minimizes interception risks compared to standard SMS, which transmits in plain text.
Not to mention, everyone is familiar with WhatsApp. Users already interact with WhatsApp daily, which means there’s no friction. OTPs arrive in a familiar chat thread, and it’s immediately recognized and encourages quick action. As a result, this limits user confusion and support requests. WhatsApp Business API also allows for OTP automation directly from your application or CRM. This means on-demand code generation, delivery, and expiration, integrated with existing authentication workflows.
How WhatsApp OTP Works
Sending a WhatsApp OTP follows a clear flow designed to verify users in real time. Here’s how it works from start to finish:
1. A User Triggers a Verification Request
The process begins when a user takes an action that requires authentication, such as logging in, signing up for an account, resetting a password, or confirming a payment.
2. The System Generates a Time-Bound Code
Your backend authentication system generates a unique one-time password. This code is time-sensitive, typically valid for 30 seconds to a few minutes, which lowers the risk of misuse if intercepted.
3. The OTP Is Sent Via WhatsApp With an Approved Template
The code is sent through WhatsApp using a pre-approved business message template. These templates comply with WhatsApp Business API rules and maintain a professional format. Delivery is near-instant, as it uses WhatsApp’s global infrastructure for high reliability.
4. The User Inputs OTP for Authentication
The user receives the code directly in their WhatsApp chat and enters it into your app or website. This step verifies that the person in possession of the WhatsApp account is the same one initiating the request.
5. OTP Code Expires After a Set Validity Period
To preserve access, the OTP automatically expires after its validity window, which prevents reuse in case of delayed or unauthorized attempts. Expired codes require a new request for a secure and controlled authentication cycle.
What You Need for Sending OTP Via WhatsApp
Before you can start sending OTP WhatsApp messages, a few essential components need to be in place. Each step guarantees compliance, protection, and smooth delivery.
1. A Verified WhatsApp Business Account (WABA)
You’ll need a WhatsApp Business Account that’s verified by Meta. This verification confirms your brand identity, unlocks higher messaging limits, and makes sure users see your business name instead of an unknown number.
2. Access to the WhatsApp Business API
The WhatsApp Business API is the foundation of OTP delivery. This is what allows your system to automatically send time-sensitive codes at scale. Most businesses get API access through a provider like Dexatel, which handles technical setup, integration, and compliance.
3. Pre-Approved OTP Message Templates
WhatsApp requires all outbound messages to use approved templates for specific use cases, like sending OTPs. These templates:
Keep your messages compliant
Include placeholders for the dynamic OTP code
Provide consistent formatting for a professional look
All of this can be done using an intuitive communications platform such as Dexatel.
4. User Opt-In Consent
Never assume that your customers or users want to hear from you out of the blue. Before sending OTPs, you must have explicit user permission to message them on WhatsApp. This opt-in can be collected during account registration, checkout, or any other relevant touchpoint. Without it, your business risks non-compliance and potential account restrictions.
Putting It Together
Once you have these four elements, you can:
Generate the OTP
Insert it into the approved template
Send it via the WhatsApp API
Track delivery and response for authentication completion
A Step-by-Step Guide to Sending OTP via WhatsApp
WhatsApp has become a preferred channel for delivering OTPs due to its consistency and strong security features. With Dexatel’s infrastructure, OTP WhatsApp delivery is globally scalable and backed by encryption. Here’s how to send OTP on WhatsApp:
1. Create and Verify Your Dexatel Account
First, go to dexatel.com and click “Start for Free.” Fill out your name, business email, and company details. Then, verify your email address via the confirmation link and complete any other verification steps in your dashboard to activate your account.
2. Register and Verify Your WhatsApp Business Account (WABA)
In the Dexatel dashboard, head over to “Add Channel,” then “WhatsApp,” and from there, go to “Get Access.” Provide your official business name, approved Facebook Business Page, and admin access to Facebook Business Manager. Next, submit a phone number not currently used with WhatsApp Messenger or the Business App. Dexatel’s onboarding team will coordinate with WhatsApp to verify your WABA, a process that typically takes five to seven business days.
3. Create and Approve Your OTP Message Template
Go to “WhatsApp Templates” in your Dexatel dashboard and click “Create Template.” Then, select “Authentication” as the category. Add placeholders for the OTP code and any other personalization fields. From there, click “Save and Send for Approval.” WhatsApp typically reviews templates within 48 hours.
4. Integrate the Dexatel WhatsApp Verify API
Next up, access Dexatel’s API or SDK documentation from your dashboard. Connect the API to your authentication system, mobile app, or website. Here, you have to activate fallback in case WhatsApp delivery fails. This means if you send an OTP via WhatsApp, and for some reason, it fails to deliver, the user still gets the OTP via SMS, for instance. After that, activate delivery reporting for real-time tracking.
5. Programmatically Trigger OTP Delivery
When a user initiates login, sign-up, or payment, your system sends an API request to Dexatel. The API generates a one-time password, inserts it into the approved template, and sends it via WhatsApp.
6. Set Personalization and TTL (Time to Live)
Include variables like the user’s name for better engagement, and define OTP expiration (for example, 60 seconds to 5 minutes) to reduce fraud risks.
7. Handle OTP Submission and Validation
When the user enters the OTP, Dexatel’s API verifies the code. If valid and within TTL, they are granted access. If the code has expired or the user entered an incorrect one, you can prompt for a new OTP.
8 Best Practices for WhatsApp OTP Delivery
1. Use Short TTL (Time to Live)
Set your OTP validity period to between 30 seconds and 5 minutes. A short TTL minimizes fraud risks by limiting the time a code can be used if intercepted. It also encourages users to complete verification promptly. Be careful to balance security with user experience—make sure the TTL isn’t so short that it frustrates users who may face delays.
2. Avoid Generic Templates
Don’t rely on bland, generic message templates. Personalization enhances user engagement. Include variable fields such as the user’s name, transaction details, or your brand name. For example, instead of “Your OTP is 123456,” use “Hi [Name], your code for [Service] is 123456.” This clarity eliminates confusion and boosts the chance that users will act quickly.
3. Guarantee Template Compliance
WhatsApp requires all OTP templates to be pre-approved and compliant with strict guidelines. Your messages must:
Avoid promotional or marketing language
Use concise wording
Include placeholders for customizable OTP codes
Be submitted for approval through your Dexatel dashboard
Non-compliance risks message rejection and delays, which affect user experience.
4. Always Provide Fallback Options
Even with WhatsApp’s global reach, some users may face internet issues or delivery failures. Always have fallback channels like SMS configured. Dexatel’s API supports automatic fallback to make sure OTPs reach users through alternate routes when WhatsApp delivery isn’t possible.
5. Limit OTP Entry Attempts
To protect against brute-force attacks, restrict the number of OTP submission attempts. After a few failed tries, lock the account temporarily or require additional verification steps. This strengthens the security of your authentication process.
6. Monitor Delivery and Response Metrics
Use Dexatel’s reports and analytics to track OTP send rates, delivery performance, and user response times. Monitoring helps identify bottlenecks or technical issues promptly so you can improve your system.
7. Have User Consent
Only send OTPs to users who have explicitly opted in to receive messages via WhatsApp. This respects privacy laws and WhatsApp’s policies, avoiding account restrictions and building trust with your users.
8. Implement Secure Data Handling Practices
While WhatsApp encrypts messages end-to-end, you still need to maintain secure storage and processing of OTPs and user data on your side. Follow best practices for data protection to complement WhatsApp’s security.
Common Use Cases of OTP WhatsApp
WhatsApp OTP has become a versatile tool for businesses aiming to reinforce security and facilitate user experience. These are the most common scenarios where OTP WhatsApp delivers real value:
Safeguarded Logins
Many platforms use OTPs sent via WhatsApp to verify users during login attempts. This way, only authorized users gain access, even if passwords are compromised.
Transaction Approvals
For financial services and eCommerce, WhatsApp OTPs confirm transactions before they’re processed. Users receive a unique code to approve payments or transfers, preventing fraud and unauthorized spending.
Password Resets
When users forget passwords, sending an OTP via WhatsApp offers a secure way to verify their identity before allowing password changes. This method is faster than email or other alternatives.
Two-Factor Authentication (2FA)
WhatsApp OTP acts as the second factor in multi-layered authentication systems. By combining something users know (password) with something they have (WhatsApp code), 2FA significantly increases account security.
Account Signups
During new account registrations, OTP WhatsApp verifies phone numbers instantly, reducing fake signups and bots. It also simplifies onboarding by delivering verification codes directly where users are active.
Key Takeaways
Thanks to its reliable performance and strong security, WhatsApp is a top choice for sending OTPs. Its global reach and high engagement rates make it an effective tool for instant user verification.
That said, success depends on following WhatsApp’s strict compliance rules, including using pre-approved message templates and obtaining user consent. Effective integration with a provider allows for dependable message delivery, fallback support, and detailed insights.
Dexatel comes with a comprehensive solution for sending OTPs via WhatsApp, which simplifies the setup and management of your verification workflows. With Dexatel’s API, you get safe and scalable OTP delivery backed by expert support.
Start sending OTPs via WhatsApp today with Dexatel and give your customers the secure verification they expect. Sign up now to send WhatsApp OTPs.
