Most WhatsApp Business conversations last 24 hours. A special Free‑Entry Point (FEP) conversation lasts 72 hours (billing‑free) when a customer comes via a Click‑to‑WhatsApp Ad or Facebook Page CTA and you reply within 24 hours. The 24‑hour customer service window still governs whether non‑template messages are allowed.

Quick navigation

• Two timers to track: 24h vs 72h
• Default durations & billing (matrix)
• Scenarios table: what you can send & what it costs
• How to verify in your UI
• API / logs (copy‑paste samples)
• Edge cases & limitations
• Expected outcomes
• Related FAQs
• Support & escalation

Two timers to track: 24h vs 72h

• 24‑hour Service window (message‑type rule): A rolling 24 hours from the customer’s most recent message. Controls whether non‑template (free‑form) messages are allowed.
• 24‑hour business‑initiated category windows (billing rule): Start at template delivery for Marketing/Utility/Authentication; each category has its own 24h window and billing.
• 72‑hour Free‑Entry Point (FEP) window (billing rule): Starts when a customer messages via CTWA/Page CTA and you reply within 24h. Billing is free for 72 hours. The 24h Service rule still applies to non‑template sends.

Key interplay: After 24h without a customer message, non‑template messages are blocked even if an FEP 72h window is still active. Use a template instead (still free under FEP).

Default durations & billing (matrix)

Scenarios table: what you can send & what it costs

How to verify in your UI

A) Meta WhatsApp Inbox

1. Open Inbox → select the conversation.
2. Find Customer Service Window: Active/Closed with a hh:mm countdown.
3. If you ran an ad or Page CTA, look for Free Entry Point — Active with a 2d:hh countdown (72h total).

B) Your provider’s dashboard (typical)

1. Open the ticket/conversation details.
2. Check service_window.status/expires_at and any free_entry flag with its expires_at.
3. If you attempt non‑template while Service is closed, the composer shows a warning; use a template.

UI Screenshot — Non‑template blocked outside 24h

Caption: After 24h, free‑form is blocked; send a template. If FEP is active, the template is free to send.

API / logs (copy‑paste samples)

Names vary by provider. Use these shapes for monitoring/alerts.

1) Service open & FEP active{ "event": "message", "customer": { "wa_id": "+15551234567" }, "service_window": { "open": true, "seconds_remaining": 21600 }, "free_entry": { "active": true, "expires_at": "2025-12-31T23:59:59Z" }, "conversation": { "category": "SERVICE" }, "pricing": { "billable": false }}

2) >24h & <72h (Service closed, FEP active → template free){ "event": "message_send_attempt", "type": "non_template", "service_window": { "open": false }, "error": { "code": "NON_TEMPLATE_NOT_ALLOWED" }, "free_entry": { "active": true }}

3) Template send during FEP (free billing){ "event": "template_delivered", "template": { "name": "follow_up_request", "category": "UTILITY" }, "free_entry": { "active": true }, "pricing": { "billable": false }}

4) ≥72h (FEP expired) → template opens paid category window{ "event": "template_delivered", "template": { "name": "promo_launch", "category": "MARKETING" }, "free_entry": { "active": false }, "conversation": { "category": "MARKETING", "opened": true, "expires_at": "2025-12-01T14:00:00Z" }, "pricing": { "billable": true }}

5) Cloud API — send a template (copy/paste){ "messaging_product": "whatsapp", "to": "+15551234567", "type": "template", "template": { "name": "follow_up_request", "language": { "code": "en" }, "components": [ { "type": "body", "parameters": [ { "type": "text", "text": "Hi Alex, just checking in." } ] } ] }}

Edge cases & limitations

• Opt‑out/Blocked: Respect user preferences; sends may be blocked regardless of windows.
• Delivery failure: If inbound or template fails delivery, the relevant conversation/state does not open/update.
• Provider variance: Some UIs hide category chips during FEP; others show them as inactive.
• Multiple categories: Category windows can overlap; re‑sending within the same category ≤24h reuses its window (no new charge).
• Time zones: Timers rely on message timestamps, not agent local time.

Expected outcomes

• ≤24h: Non‑template allowed; templates billed per category (unless FEP is active → free).
• >24h & <72h (FEP active): Non‑template blocked; templates send free.
• ≥72h: Templates open a paid category window; non‑template stays blocked until the customer replies.

Related FAQs

• What is conversation‑based pricing on WhatsApp Business API?
  /help/whatsapp/conversation-pricing
• What is a Free‑Entry Point conversation?
  /help/whatsapp/free-entry-conversation
• When do I need to use a message template?
  /help/whatsapp/when-to-use-templates
• What opens a Service conversation?
  /help/whatsapp/service-conversation-opens

Support & escalation

If behavior differs from this FAQ or sends fail unexpectedly, open a Support ticket from your admin portal (attach message IDs, timestamps, pricing logs, and screenshots), or contact your Customer Success Manager. Typical response time: 1 business day.