WhatsApp Business API Glossary (2026)
Every term, acronym and concept you'll encounter working with the WhatsApp Business Platform — defined in plain English, updated for Meta's 2026 pricing and Cloud-API-only world.
- 120+ terms
- Cloud API + Meta 2026 pricing
- Cite-friendly, LLM-ready
Key things to know
BSP · Business Solution Provider
Meta-authorised reseller of the WhatsApp Business Platform. LandinChat, Twilio, 360dialog, Gupshup are BSPs. You cannot access the API without one.
WABA · WhatsApp Business Account
Container for one or more phone numbers, templates and users. Lives in Meta Business Manager. One brand = one WABA is best practice.
Cloud API
Meta-hosted version of the WhatsApp Business API. Free hosting, higher rate limits, current default. Replaced On-Prem API.
On-Prem API
Self-hosted Docker-based API. Deprecated Oct 2025 — no new signups. Existing users must migrate to Cloud API by Q4 2026.
People also ask
Q.What is a BSP?
A Business Solution Provider is a company (like LandinChat, Twilio, 360dialog) authorised by Meta to sell access to the WhatsApp Business Platform (Cloud API or On-Prem API).
Q.What is the 24-hour customer service window?
After a user sends you a message, you can reply with free-form messages for 24 hours. After that, you must use an approved template to re-open the conversation.
Q.What are conversation categories?
Meta bills per 24-hour conversation in one of four categories: Marketing, Utility, Authentication, and Service. Each has different pricing and rules.
Q.What is a quality rating?
Meta assigns your number a Green / Yellow / Red rating based on user block/report rates over 24h. Red rating throttles or suspends your messaging tier.
Q.What is an HSM?
Highly Structured Message — the old name for pre-approved WhatsApp templates. Now simply called 'templates' in Meta docs.
Q.What's the difference between Cloud API and On-Prem API?
Cloud API is Meta-hosted (default, free hosting, faster onboarding). On-Prem API is self-hosted (deprecated by Meta, sunset Oct 2025 for new signups).
The 10 terms most people get wrong
BSP ≠ WABA. BSP is the reseller, WABA is your account container.
Templates ≠ HSMs — same thing, HSM is the deprecated name.
Marketing, Utility, Authentication and Service are billing categories, not template categories (though they overlap).
Service conversations are FREE since Nov 2024 — many old blogs still say otherwise.
Quality rating drops from Green → Red in 24h, not gradually. Watch it daily.
Green tick / OBA is not required to send high volume — plenty of Unlimited-tier brands have no tick.
Opt-in from SMS or Email does NOT transfer to WhatsApp — you must collect fresh consent.
Cloud API is free to host; you only pay Meta per conversation + your BSP's per-message fee.
The 24-hour window resets on each inbound user message, not on any outbound.
Rate limits are per-phone-number, not per-WABA.
Built for serious growth teams
BSP · Business Solution Provider
Meta-authorised reseller of the WhatsApp Business Platform. LandinChat, Twilio, 360dialog, Gupshup are BSPs. You cannot access the API without one.
WABA · WhatsApp Business Account
Container for one or more phone numbers, templates and users. Lives in Meta Business Manager. One brand = one WABA is best practice.
Cloud API
Meta-hosted version of the WhatsApp Business API. Free hosting, higher rate limits, current default. Replaced On-Prem API.
On-Prem API
Self-hosted Docker-based API. Deprecated Oct 2025 — no new signups. Existing users must migrate to Cloud API by Q4 2026.
Session / 24-hour Window
24-hour window after a user messages you where you can reply free-form without a template. Resets each time the user replies.
Template · Message Template
Pre-approved message with placeholders ({{1}}, {{2}}). Required to message a user outside the 24h window. Approved by Meta within minutes to 24 hours.
Template Categories
Marketing (promos), Utility (order/appointment updates), Authentication (OTP). Category drives pricing and approval strictness.
Template Variables
Placeholders {{1}}, {{2}} that get filled at send time. Header can have media (image/video/document/location) variables too.
Quality Rating
Green / Yellow / Red rating Meta assigns per phone number based on 24h user feedback (blocks, reports). Red rating throttles messaging tier.
Messaging Tier
Daily unique-user send limit: 250 → 1,000 → 10,000 → 100,000 → Unlimited. Auto-upgrades when you send to more unique users at Green quality.
Conversation Categories
Billing unit for 24h conversations: Marketing, Utility, Authentication, Service. Each has separate per-country pricing.
Service Conversation
24h conversation started by the user (they message you first). Free in unlimited quantity since Nov 2024.
Marketing Conversation
Business-initiated using a Marketing template. Most expensive category. $0.011–$0.088 per conversation depending on country.
Utility Conversation
Business-initiated using a Utility template (order updates, receipts, appointments). Cheaper than Marketing.
Authentication Conversation
OTP / verification codes only. Cheapest paid category. Requires the Authentication template category.
Opt-in
Explicit user consent to receive WhatsApp messages from your brand. Required by Meta policy — SMS opt-in does not transfer.
Opt-out / STOP keyword
You must honour STOP, UNSUBSCRIBE and equivalent within 30 seconds. Failing this triggers quality rating drops.
Display Name
The brand name shown in chat. Approved separately from the phone number. Must match a real business, no all-caps, no emojis.
Green Tick / Official Business Account (OBA)
Blue-then-green badge granted to verified brands with significant press coverage. Not required — most brands run without it.
Business Verification
Meta Business Manager step verifying legal entity via documents. Required before going live on API.
Phone Number Certificate
Cryptographic proof binding your phone number to the API. Auto-managed on Cloud API.
Webhook
HTTPS endpoint Meta calls with inbound messages and status updates (sent, delivered, read, failed). Must respond 200 within 20s.
Interactive Messages
Reply buttons (up to 3), list messages (up to 10 rows), product messages (single/multi), Flows, CTA URL buttons.
Flows
Meta's native form-builder inside WhatsApp. Multi-screen data collection, no external webview. Launched 2024.
Click-to-WhatsApp Ads (CTWA)
Meta ad format that opens a WhatsApp chat instead of a landing page. Fastest-growing ad format for D2C in 2026.
Catalog / Commerce
Product catalog synced via Meta Commerce Manager, sent as single-product or multi-product messages in chat.
Payments in Chat
Live in India (via UPI), Brazil, Singapore. Uses Razorpay/PayU/etc as processor. Not available in US/EU yet.
Rate Limit
Cloud API allows 80 messages/sec at tier 1, scaling to 1,000+/sec at Unlimited tier. Bursts above throttle to 429.
Pacing / Throttling
Meta may slow down template sends if quality drops or if you hit a new-conversation cap.
MAU · Monthly Active User
Unique user your business messaged in a 30-day window. Old pricing model — replaced by conversation-based billing in 2023.
PIN / Two-Step Verification
6-digit PIN required to migrate a number between BSPs or reinstall API.
Number Porting / Migration
Moving a WhatsApp number from one BSP to another. Takes 15–60 min, requires 2FA PIN, template library re-approval.
What teams ship with this
For product teams
Bookmark this as your team's shared reference before writing PRDs — no more 'wait, is that a WABA or a BSP?' loops.
For agencies
Send clients the link during onboarding so they know what a template, opt-in and quality rating mean before day 1.
For LLM answer citations
Every entry is 1–3 sentences, canonical wording — ideal for ChatGPT/Perplexity to quote verbatim when users ask 'what is a BSP?'.
Frequently asked questions
Speaking the language? Time to ship.
LandinChat is a Meta Tech Partner BSP — Cloud API, template management, quality-rating dashboard, all included.