A CTWA campaign runs through Meta Ads Manager like any Facebook or Instagram ad, but the tap destination is a WhatsApp thread with the business, usually pre-filled with a starter message. The resulting conversation arrives with ad-level referral data attached, so responses can be routed, attributed, and measured back to the specific creative that produced them.
The free entry point window. Under Meta's per-message pricing, when a user starts the chat from a CTWA ad on a mobile device, a standard 24-hour customer service window opens. If the business replies within those 24 hours, that reply is free and a free entry point window opens: for 72 hours, every message type — including marketing and utility templates — can be sent at no charge. Chats initiated from WhatsApp desktop or web clients do not qualify.
Why speed decides the economics. The clock starts at the first user message, so an instant automated greeting or AI agent captures the free window, while a reply that comes a day late forfeits it. Well-built CTWA funnels aim to qualify leads, answer objections, and close inside those 72 hours, before any message fees accrue.
Why it matters for brands
CTWA turns paid social into an owned conversation instead of a bounced landing-page visit, and the 72-hour free window makes fast, automated response the cheapest acquisition path into WhatsApp.