Written guides on how the WhatsApp Business Platform behaves, kept current as it changes. Each chapter is its own page, with a copy button so you can hand the full text to your LLM.
9 chapters · 35 min · 1 with video
What WhatsApp messaging actually costs: how Meta assigns a price to every message, why that price is decided after delivery rather than at send time, and what changes when service messages become billable on October 1, 2026.
0. How pricing works today
1. What changes on October 1
7 chapters · 31 min · 1 with video
Meta is replacing the phone number as the identity key on the WhatsApp Business Platform. The new identifiers have been arriving in your webhooks since April 2026, and the phone number is only now starting to disappear. This guide covers the whole migration: how to read, store, match and message a business-scoped user ID.
0. Introduction
1. Identity