WhatsApp API Send Message Explained: Step-by-Step Guide for 2025

Importance of WhatsApp API for businesses   

According to Vogue Business, Reliance Brands Limited used the WhatsApp API to overcome the challenges of physical store closures during the COVID-19 pandemic by enabling "distance selling" through video calls and interactive catalogs, resulting in over 20,000 transactions. This solution allowed them to maintain customer engagement and sales, even during periods of restricted in-store activity, highlighting WhatsApp's role in driving revenue and customer interactions. 

The WhatsApp Business API enables businesses to manage communication at scale while maintaining the human touch. Whether you are a tiny startup or a multinational company, using WhatsApp API can help build a loyal customer base by ensuring you respond to their queries instantly. Let us now look at the key benefits of WhatsApp API for businesses.   

1. Register with a WhatsApp Business Solution Provider (BSP)    

Since the WhatsApp API is not directly available to use like the regular app, businesses need to rely on an official WhatsApp Business Solution Provider (BSP) such as Gallabox. These BSPs bridge the gap, give businesses the appropriate access to the API, and assist in adhering to WhatsApp's message-sending guidelines.  

2. Get API credentials    

After businesses register with a BSP, they receive API credentials, including an authentication token and a unique business number linked to WhatsApp. Think of this as your key to accessing the API securely.    

3. Set up webhooks for real-time notifications    

You can configure webhooks to notify you instantly about customer interactions with your messages. Setting up webhooks helps businesses in tracking:   

• When a message is delivered   

• Whether a message is read and when  

• Reply and engagement    

This is important for responding automatically and having streamlined customer conversations.   

4. Create a message template (for business-initiated messages)    

If your business starts the conversation, WhatsApp requires you to use pre-approved message templates. These templates also prevent spam and help enterprises send relevant and high-quality messages. Examples include:    

• Order confirmations    

• Shipping updates    

• Appointment reminders    

But if an individual customer messages you first, you can respond with any message you like and without a template — just like in a regular chat!   

5. Send a message using the API    

The process is straightforward. Now, you can send messages with a simple HTTP request. It's like firing off a regular chat message, though obviously on a much larger scale. Once you send your request, WhatsApp immediately zips the message to the recipient, resembling your everyday chat but powered up for large-scale sending. 

6. Monitor delivery & responses    

You can monitor delivery and response rates after a message has been delivered through a WhatsApp API platform or via webhook notifications. This allows you to track client engagement and systematically improve your messaging strategies.  

Mastering the WhatsApp API involves an initial learning curve. But once set up, it revolutionizes business communication. Whether you're sending order status, customer service replies, or promotions, automation, efficiency, and scalability make it a vital tool for businesses today.  

Breaking it down: What each part means   

• messaging_product: "WhatsApp" → Specifies that this message is being sent via WhatsApp.    

• recipient_type: "individual" → This means the message is for a single user, not a group.    

• To: "1234567890" → The recipient's phone number (including country code but without the + sign).    

• Type: "text" → This tells WhatsApp the message format (in this case, a simple text message).    

• Text: {"body": "Hello, this... } → This is the actual message content that the user will receive.  

Sending rich media messages   

The WhatsApp API isn't limited to just text. You can send images, PDFs, videos, or even interactive buttons. According to ElectroIQ, around 65% of businesses using the WhatsApp Business API are sending marketing messages that include multimedia content such as images, videos, or documents. 

What’s next after sending?   

After Meta approves your API request:  

• The system sends the message to the receiver in real-time.  

• You will receive a delivery confirmation through your webhook.  

• When the customer responds, you can respond automatically or interact with them manually.  

1. Appointment reminders and rescheduling

Healthcare clinics, beauty salons, and service centres can use the API to auto-send reminders before appointments - and even allow customers to confirm, reschedule, or cancel through interactive buttons.

2. Billing and invoice alerts

Automatically notify customers when a new invoice is generated, a bill is due, or a payment has failed. This is especially valuable for fintech apps, subscription services, and B2B SaaS platforms. For example, SumUp, a UK-based fintech company, implemented the WhatsApp Business API to share payment links to ease the overall payment process.

Given below is an example of a WhatsApp message sent using the API, sharing the link to the invoice generated after a purchase:

3. Product back-in-stock and price drop alerts

Let customers know when a product they liked is back in stock or goes on sale. These highly personalized alerts boost return traffic and increase conversion rates without additional ad spend. E-commerce companies use this as a hack to bring users back to the platform to improve sales and reduce cart abandonment.

4. Internal alerts for field teams

You can use the API to send task updates, schedule changes, or customer visit details to internal teams, such as field service agents, delivery staff, or sales reps - all within WhatsApp.

5. Event RSVP confirmations and reminders

Planning a webinar, store launch, or workshop? Use WhatsApp to send invitations, collect RSVPs, and send countdown messages to maximize attendance and engagement. For example, payment gateway platform Razorpay actively uses WhatsApp to send out communications about events, as shown in the image below:

6. Post-service feedback and ratings

After a service or delivery, you can send a short message using the WhatsApp Business API asking for customer feedback or a quick CSAT rating. These timely nudges yield higher response rates than email surveys. Have a look at the screenshot below as an example:

These use cases show how flexible the WhatsApp API can be, not just for customer support, but for every stage of the customer and employee journey.

1. Obtain a clear opt-in   

Before reaching out to customers, ensure you have their explicit consent. WhatsApp requires businesses to collect opt-ins clearly and transparently. This means:    

• Informing users that they agree to receive messages from your business via WhatsApp.    

• Clearly state your business name at the point of opt-in.   

• Global data privacy regulations (e.g., General Data Protection Regulation, California Consumer Privacy Act) should be followed to protect customer rights.    

Opt-in methods can include website sign-ups, in-app confirmations, or QR codes, but users should know exactly what they're signing up for.    

2. Use pre-approved message templates   

To avoid unsolicited messages, try WhatsApp-approved message templates to start conversations. These are great for transactional messages like:   

• Order confirmations and shipping updates.    

• Appointment reminders and booking confirmations.    

• Secure login experiences with payment alerts and One-time passwords (OTPs). 

3. Personalize your messages   

According to Shopify’s report ‘The Future of Personalization Is Here: The Trends to Look Out for in 2025,’ 81% of consumers say they are willing to spend more with businesses that offer better, more personalized experiences. Nobody enjoys chatting with a cold, robotic system. A little personalization goes a long way in building trust and keeping customers engaged. Here's how you can make your messages feel more human:  

• The customer's name is a slight touch that makes a big difference.  

• Take references from their past purchases to show that you remember them.  

• Go for tailored recommendations or exclusive deals based on their interests.  

The more relevant your message, the more likely customers will connect with your business.  

4. Respect the 24-hour rule   

WhatsApp has a 24-hour customer care window. When a customer messages your business, you can message back freely within this window. But if you want to send messages beyond this time frame, you must use an approved template.  

To maximize customer engagement:  

• Reply to customer queries quickly.  

• Use automation and chatbots for quick replies.  

• Transition to live agents when needed to keep it human.  

💡Interesting fact: Medium and large businesses are projected to spend $3.6 billion on WhatsApp Business services in 2024, indicating the platform's growing importance in corporate communication strategies - Analyzify 

5. Maintain a high-quality rating   

WhatsApp monitors how users respond to your messages, paying attention to negative feedback like blocks or reports.   

If your quality rating drops due to such feedback, your account might face restrictions or even suspension. To keep your rating high:  

• Avoid sending too many messages or spamming users.    

• Prioritize value-driven messages like order updates and support over frequent promotions.    

• Monitor engagement metrics and adjust messaging strategies accordingly.    

WhatsApp categorizes quality ratings into three levels:    

• Green (High quality) – No issues.    

• Yellow (Medium quality) – Some reports, but still acceptable.    

• Red (Low quality) – High negative feedback may lead to restrictions.    

6. Follow messaging limits and tiers   

WhatsApp has rules about how many people a business can send daily messages to. You can move up to a higher messaging level as you engage with more people successfully. Here are the levels:    

• Tier 1: 1,000 unique users per day.    

• Tier 2: 10,000 unique users per day.    

• Tier 3: 100,000 unique users per day.    

• Tier 4: Unlimited messaging.    

To expand your business reach, your WhatsApp messages need to be high-quality and engaging for your audience.    

7. Ensure compliance with WhatsApp's policies   

Several businesses have reported their WhatsApp Business accounts being blocked due to policy violations (please see an example here). Ignoring WhatsApp rules can result in permanent restrictions. Remember these critical points to keep things neat and positive on this platform.  

• Businesses should not send unsolicited promotional messages. 

• You should also not send misleading, fraudulent, or deceptive content. 

You should always review WhatsApp's latest business messaging policies to ensure compliance.      

8. Use automation and chatbots wisely   

According to Virtue Market Research, approximately 80% of users prefer interacting with businesses through chatbots on WhatsApp, citing convenience and speed as primary reasons. At the same time, chatbots should enhance—not replace—the human experience. Best practices include:    

• Using AI-driven bots for FAQs and simple queries.    

• Escalating complex issues to human agents.    

• Ensuring messages are conversational and user-friendly.    

9. Optimize timing and frequency   

Even if a customer has opted in, you will be blocked if you spam them with messages! Instead:    

• Customize the time of messages to the customer's current location.  

• Don't follow up aggressively.    

• Track engagement rates to discover the most effective dispatch times.    

10. Leverage rich media and interactive messages   

WhatsApp allows businesses to send images, videos, and interactive buttons. This can enhance the user experience by:    

• Providing visual product catalogs.    

• Leveraging quick-reply buttons for faster engagement.    

• Using list messages to offer multiple options without overwhelming the user.    

Interactive messages make communication more straightforward and can lead to higher conversion rates.  

WhatsApp API is a powerful tool for customer engagement, but only when used strategically. By following these best practices—gaining opt-ins, personalizing messages, maintaining quality ratings, and respecting WhatsApp's policies—you can maximize the effectiveness of your business communications.   

1. Can I send messages without saving numbers?   

Yes, businesses can send messages via the WhatsApp Business API without saving numbers. This makes customer interactions more scalable, with the ability to reach thousands of users at once.  

 2. Can I send interactive messages?   

One of the key differentiators of the WhatsApp Business API is its ability to send messages in interactive formats such as lists, buttons, and rich media (like videos, PDFs, and images). This improves the overall chat experience and ensures users stay engaged throughout.  

 3. Can messages be sent in different languages?   

Yes, businesses can send multilingual messages through the API. Since WhatsApp is present in over 180 countries, it is very much a global application. This has encouraged the platform to build capabilities in multiple languages, ensuring that cultural and linguistic diversity is considered.  

 4. Does the API support media files? 

As mentioned above, you can send images, videos, PDFs, and other attachments to enhance the effectiveness of your communication efforts. This eases information sharing by giving users access to all the details they need within the app instead of visiting external links or resources. This enhances trust since users do not have to click on untrustworthy links.  

 5. Can I integrate WhatsApp API with my CRM?  

Absolutely. The API allows seamless integration with CRM systems, chatbots, and automation tools. Data can be transferred between WhatsApp, CRMs, and any business applications in real time to ensure users get a personalized experience. Integrations also help businesses create a single pane of view of all their customer interactions.  

 6. How secure is WhatsApp API messaging? 

WhatsApp encrypts all messages end-to-end, ensuring private and secure communication. In addition, WhatsApp requires you to use pre-approved message templates if you are initiating the communication. This step ensures businesses don’t bombard users with unnecessary and irrelevant messages.