How to Send OTP Messages on WhatsApp: A Complete Guide for Businesses

One-Time Passwords (OTPs) are a critical part of secure customer authentication. From logging into accounts to completing high-value transactions, OTPs help businesses prevent fraud and deliver safer digital experiences.

With WhatsApp now supporting OTP delivery through the WhatsApp Business API, businesses can send fast, reliable, and highly engaging authentication messages directly to users’ phones.

In this guide, you’ll learn how to send OTP messages on WhatsApp, why it’s better than SMS, and how to set it up using AiSensy.

What Is an OTP Message on WhatsApp?

An OTP (One-Time Password) is a unique, time-sensitive code sent to a user to verify their identity during:

• Login or account registration
• Password resets
• Payment confirmations
• Two-factor authentication (2FA)

When delivered through WhatsApp, OTPs reach users faster than traditional SMS and appear inside a trusted, high-engagement messaging platform.

Why Send OTP Messages on WhatsApp Instead of SMS

Businesses worldwide are switching from SMS to WhatsApp for OTP delivery because of the following advantages:

Higher delivery rates
WhatsApp messages typically have higher delivery success compared to SMS, especially in regions with unreliable carrier networks.

Faster delivery times
OTP messages on WhatsApp are delivered almost instantly, reducing user friction during login and checkout.

Cost-effective at scale
WhatsApp often becomes more economical than SMS for businesses sending high volumes of OTPs.

Rich and branded experience
You can include your brand name and verified business account to build trust during authentication.

How WhatsApp OTP Works with WhatsApp Business API

To send OTP messages on WhatsApp, businesses need access to the WhatsApp Business API. Unlike the WhatsApp Business App, the API allows:

• Automated OTP delivery
• Integration with your website or app
• Use of pre-approved message templates

Platforms like AiSensy make this process simple by removing technical complexity and helping you go live faster.

Tutorial: How to automate Authentication WhatsApp Template messages?

How to Send OTP Messages on WhatsApp Using AiSensy

Sending OTP messages on WhatsApp becomes seamless when you use AiSensy’s Authentication Templates and API automation. You can create secure, pre-approved OTP templates and trigger them automatically from your website or app in just a few steps.

Below is a simplified step-by-step guide to help you set up WhatsApp OTP messages using AiSensy.

Step 1: Create an Authentication Template in AiSensy

Start by creating your WhatsApp Authentication template inside the AiSensy dashboard:

1. Go to Manage → click Template Message
2. Click + New to create a new template
3. Under Template Category, select Authentication
4. Under Template Type, choose Text
5. Select your desired template language
6. Enter a template name (lowercase, alphanumeric, no spaces or special characters)
7. Add a sample OTP code (this is only for approval, not the real code)
8. (Optional) Add an OTP expiration warning and a short security message asking users not to share their code
9. Under Interactive Actions, enter your sample code in Copy Code
10. Submit the template for approval

Most templates are approved within seconds, but it can take up to 24 hours in rare cases.

Step 2: Set Up an API Campaign for OTP Automation

Once your Authentication template is approved, you can automate OTP delivery via API:

1. Go to Campaigns → click + Launch → select API Campaign
2. Enter a campaign name
3. Select your approved authentication template
4. Set the campaign live

Step 3: Test Your WhatsApp OTP Campaign

Before going live, test the OTP flow to ensure accuracy:

1. Open your campaign and click Test Campaign
2. In the script that appears, find the templateParamsarray
3. Insert your sample OTP code between the double quotes
4. Locate the button parameters section and insert the same OTP code again
5. Save your changes

This ensures both the message body and interactive button display the correct code.

Step 4: Connect the cURL to Your Backend

Now link your system with AiSensy to send OTPs automatically:

1. Copy the generated cURL
2. Paste it into your backend where OTPs are triggered (login, signup, payments, etc.)
3. Dynamically map user fields such as mobile number and username to ensure each user receives a unique OTP on their WhatsApp number
4. Test with your own WhatsApp number before going fully live

Once this cURL is connected, your WhatsApp OTP automation goes live instantly.

Best Practices for WhatsApp OTP Messages

To maximize security and user experience, follow these best practices:

• Keep OTP codes short (4–6 digits)
• Set expiry times (usually 5–10 minutes)
• Always include a warning not to share the code
• Use clear branding in the message
• Implement retry and rate-limiting logic

Sample WhatsApp OTP Message Templates

Here are ready-to-use templates you can adapt:

Login OTP

"Your login code for {{Business Name}} is {{1}}. Valid for {{2}} minutes. Please do not share it with anyone."

Transaction OTP

"To complete your transaction, enter this verification code: {{1}}. This code expires in {{2}} minutes."

Password Reset OTP

"Use {{1}} to reset your password. This code is valid for {{2}} minutes. If you didn’t request this, please ignore the message."

Final Thoughts

WhatsApp OTP messages are faster, more reliable, and more secure than traditional SMS, making them a powerful upgrade for any business that values both security and user experience. If your goal is to reduce drop offs during login, sign up, or checkout, switching to WhatsApp authentication is a smart and future proof move.

With AiSensy, you can easily send OTP messages on WhatsApp and automate the entire verification flow in just a few minutes. Create a free AiSensy account today and start delivering secure, instant OTPs that your customers already trust and love.

FAQs About WhatsApp OTP

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