WhatsApp Message Templates and Sessions. 8 min read

WhatsApp Business messaging operates on a fundamentally different model than email or SMS. You can't simply send a message to anyone at any time. WhatsApp enforces a conversation-based pricing model with strict rules about when businesses can initiate contact.

There are two types of messages: template messages and session messages. Understanding the difference is critical for any business using WhatsApp as a communication channel.

Template messages are pre-approved message formats that businesses use to initiate conversations with customers. Every outbound message that starts a new conversation must use an approved template. You submit templates to Meta for review, and they're typically approved within minutes to hours.

Templates fall into categories that determine pricing: utility (order confirmations, shipping updates), authentication (OTP codes, account verification), marketing (promotions, product recommendations), and service (customer support responses). Each category has different per-message rates that vary by country.

Template messages can include variables for personalization — customer name, order number, product details — but the structure must match the approved template exactly. You can include buttons (quick replies and call-to-action URLs), headers (text, image, video, or document), and footers.

The key constraint: template messages are for business-initiated conversations. You pay the conversation rate when you send the first template message, which opens a 24-hour conversation window.

When a customer messages your business first, it opens a free 24-hour service window. Within this window, you can send any message — no template required. This is the session messaging model, and it's where customer service and interactive commerce happen.

The 24-hour window resets with each customer message. So an active conversation can continue indefinitely as long as the customer keeps responding. But if 24 hours pass without a customer message, the window closes and you need a template message to re-initiate.

Session messages are free from the business side (the customer never pays). This makes WhatsApp particularly cost-effective for customer service: the customer initiates, you respond within the session window, and there's no per-message charge. The cost structure incentivizes responsiveness — respond quickly while the session is open rather than waiting and needing to use a paid template.

Maintain a library of approved templates for common use cases: order confirmation, shipping notification, appointment reminder, feedback request, and a small set of marketing templates. Having pre-approved templates ready means you can launch campaigns quickly without waiting for Meta's review process.

Keep marketing templates relevant and personalized. Generic promotional templates get lower quality scores from Meta, which can increase your costs and reduce your sending limits. Templates that include customer-specific variables and clear value propositions maintain higher quality ratings.

Monitor your template quality scores in the WhatsApp Business Manager. Templates that generate blocks or complaints get downgraded, which restricts your sending capacity. If a template drops below acceptable quality, pause it, revise the content, and submit a new version rather than continuing to send with a low-quality template.