WhatsApp 24-Hour Session: Rules, Reset, and Billing

01 · Glossary

How the window opens

The customer opens it, not you.

• Any inbound customer message opens the window
• The clock runs 24 hours from the last customer message
• Each new customer message resets it to a full 24 hours
• Click to WhatsApp, QR, and wa.me entries all open the window

02 · Glossary

What you can do inside the window

The open window is the cheapest and most flexible state in WhatsApp.

• Reply with free-form text, images, and links
• No template approval needed
• No conversation fee for the service conversation
• Product, price, and support questions all flow free

03 · Glossary

What happens when it closes

The window closing changes the rules of the game.

• Free-form business-initiated messages become impossible
• Any new business message must be an approved template
• The template send opens a new conversation billed by category
• Marketing, utility, and authentication each bill at their own rate

04 · Glossary

Keeping the window open profitably

A fast team turns the window into a free service channel.

• Answer promptly: every reply invites another customer message
• Use quick replies and canned responses to answer instantly
• Move order updates and reminders into the window where possible
• After-hours automations keep the conversation alive when the team sleeps
• Wutt flags closing windows in the inbox so nothing drifts past 24 hours

Last updated 5 August 2026