Traditional advertising often loses potential customers on the way to a purchase: the website takes too long to load, the request form feels too long, and people would rather not answer calls from unknown numbers. Moving the conversation to a messenger changes this approach entirely.
CTWA (Click-to-WhatsApp) is a special ad format on Facebook and Instagram that, when someone clicks the ad, instantly opens a WhatsApp chat with a pre-filled first message.
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Why It Works for Customers and Pays Off for Businesses
The main advantage of CTWA is that everything happens in a single click. The customer doesn’t waste time filling out forms, and the business gets the contact’s identifier and an open conversation after the user’s first message.
What’s more, over 90% of users open WhatsApp messages (Source: https://business.whatsapp.com/whatsapp-vs-whatsapp-business), because people are far more comfortable chatting in a familiar app than waiting for a call from an operator.
In addition, when a customer sends a message from a CTWA ad, a 72-hour free entry point window opens on the WhatsApp Business Platform. Messages the business delivers during this period are not charged by Meta. Within this window, you can send special offers, collect feedback and guide the customer toward repeat purchases.
Key Use Cases
The format is versatile and adapts to a wide range of business goals.
In lead generation mode, an automated bot or a manager instantly picks up the conversation, identifies the customer’s needs and builds a database of qualified contacts.
In consultative selling, experts join the conversation, which is ideal for complex, high-ticket products where buyers need to ask questions first.
The format also works great for discount promotions, where a promo code delivered instantly in the chat encourages a quick purchase.
Finally, it is used for building loyalty, creating a fast support channel that makes the company stand out from its competitors.

Conclusion
The Click-to-WhatsApp format helps businesses stop losing traffic on complicated website forms and instead move interested users straight into a personal conversation, guiding them to a purchase in an environment they already know.
GREEN-API lets you receive and automatically process messages that come from CTWA ads. The ad message data includes an ad referral flag, the ad ID, the source app and the ctwaClid parameter, which lets you link the conversation to the ad campaign. This data can be passed to a CRM and used to route inquiries and launch a chatbot.