Templates, sessions, and 24-hour windows — short glossary
WhatsApp Business Platform documentation is written for developers. This glossary is written for owners. Each term in one or two lines, current as of October 2026, based on Meta’s developer docs.
The basics
WhatsApp Business app. Meta’s free app for small businesses: profile, catalogue, labels, quick replies. Runs on a phone.
WhatsApp Business Platform. The business-grade setup, where your number connects to software. People often just say “the API”.
Cloud API. Meta’s hosted API for sending and receiving WhatsApp messages and calls on your business number.
Business Solution Provider (BSP) / Tech Provider. A company approved to connect businesses to the platform. Most SMEs use one instead of building directly.
Business portfolio. Your business’s container in Meta’s systems, holding your WhatsApp and messaging accounts.
Coexistence. Using the WhatsApp Business app and Cloud API on the same number, with history kept in sync. Needs a provider that supports it.
Messages and windows
Customer service window (CSW). A 24-hour window that opens when a customer messages you and resets with each new customer message. Inside it you can send normal replies.
Service message. A normal, non-template reply sent inside the customer service window, whether typed by staff or written by a third-party AI.
Template message. A pre-written message, usually approved in advance, that you can send at any time. Templates are the only way to message a customer outside the window.
Template categories. Marketing (promos, offers), Utility (order updates, booking reminders), Authentication (one-time passwords). The category affects the price.
Session / conversation. Older terms from when Meta charged per 24-hour “conversation”. That model was replaced by per-message pricing on 1 July 2025, but many guides still use the words.
Free entry point (FEP) window. Opened when a customer messages you from a Click-to-WhatsApp ad or a Facebook Page call-to-action button and you reply within 24 hours. For 72 hours, message delivery is free. It runs separately from the customer service window.
Opt-in. The customer’s permission to receive your templates. Meta requires it, and it must make your business name and intent clear.
Pricing terms
Per-message pricing. Since 1 July 2025, Meta charges when a template message is delivered, with rates by category and the recipient’s country code.
Service message charges (new). From 1 October 2026, Meta charges per delivered service message as well, at the same rate as utility and authentication messages in that market. Utility templates sent inside the window are charged from that date too.
Meta Business Agent. Meta’s own AI agent product on WhatsApp, charged per token since 1 August 2026. Replies written by a third-party AI (like ThinkChat) count as service messages, not Meta Business Agent messages.
Rate card. Meta’s published list of per-message rates by market. Rates may be updated up to quarterly.
Limits and quality
Messaging limit. How many unique customers you can reach with templates (outside the window) in a moving 24-hour period.
Quality rating. Meta’s rating for each business number and template. Meta uses it when deciding automatic throughput upgrades, so sending messages customers actually want pays off.
Throughput. How many messages per second a number can send. Meta’s docs list 80 per second by default. That is plenty for SMEs.
What this means for you
- Reply while the window is open. It’s the easiest, friendliest way to serve a customer.
- Use templates for reminders and updates customers asked for, not cold blasts.
- Ask your provider how Meta’s charges show up on your bill, especially since 1 October 2026.
For the bigger picture, read WhatsApp Business API in plain English and What changes when you leave the WhatsApp phone app.
Soft next step
If you’d rather have someone else worry about windows and templates, Talk to Lyia on WhatsApp: +60 11-5515 9318.
Plans stay simple: Junior RM299 · Senior RM599 · Manager RM899 a month. Pick the level that matches how much of your customer service you want covered.