In this knowledge base we explain what the WhatsApp Business API is, what it costs, how to apply for it, and which rules Meta sets for messages, templates, and consent. Every page opens with the short answer and then goes deeper, with a visible last-updated date.
Starting at the beginning
The definition, what you use it for, and what you need.
View →When the free app is enough and when you need the API.
View →How a mapped-out conversation works, and the two meanings of “flow”.
View →Costs and rules
The four message categories, worked examples, and where you can save.
View →Why this window largely decides your costs.
View →Categories, approval, and the most common rejections.
View →Applying and compliance
A seven-step guide, pitfalls included.
View →When consent is valid, and what you don't share over WhatsApp.
View →From theory to practice: seven flows with message copy.
View →How we maintain these pages
Meta changes its rules and rates regularly. That's why every page carries a last-updated date and why we avoid quoting amounts that go stale quickly. Spot something that's no longer right? Let us know.
Frequently asked questions
Who is this knowledge base for?
For owners and marketers at small and medium-sized businesses who want to automate WhatsApp and understand first how it works and what it costs — without a demo request standing in the way.
Is this independent information?
We sell a flow builder, so we have a stake in this. That's why we keep the explanations factual, say what isn't possible as well, and mark clearly where we're writing about our own product.